Bulletin of the Atomic Scientists: The Doomsday Clock stays at 90 seconds before midnight

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Tuesday January 23, 2024 · 10:43 AM PST

2024/01/23 · 10:43

The Doomsday Clock was set this a.m. It's 90 seconds to midnight.

The Doomsday Clock setting for this year (based on events in 2023) was once again set at 90 seconds ‘til midnight, the same as last year.

I recommend listening to the broadcast when you have an opportunity. There is also a written summary with links to webpages with more details on each area of concern. Briefly, the contributions to the clock-setting were familiar:

Global conflicts, especially in Ukraine and the Middle East, and potentially in Taiwan potentially could escalate to use of nuclear weapons
Global warming continues unabated, with 2023 being the warmest year in the official instrumental record. It was also one of, if not THE, warmest years in the 24,000 year reconstructed record, as we can see below. Note the 1,000-year cooling about 13,000 years ago (called the Younger Dryas), which was probably caused by a massive flux of fresh water from the melting glaciers over North America, which caused a temporary shutdown of the meridional ocean circulation.

On a more positive note, the U.S. saw its global warming emissions decrease 1.9% in 2023 because of a decrease in coal and increased renewables in the energy mix.

Caption from Phys.org. The blue line shows globally averaged surface air temperature since the last ice age, 24,000 years ago, created by assimilating paleoclimate records with a computer model of the climate system. Time is stretched for the past 1,000 years to visualize recent changes. Warming begins at the end of the last ice age, roughly 18,000 years ago, then temperatures stabilize.While previous studies showed a slight cooling over the past 10,000 years, the new analysis shows a slight warming trend. The curve steepens in recent decades with the accumulation of atmospheric greenhouse gases. Credit: Phys.org; Osman et al./Nature.

Biological threats, both natural and from human research, may cause pandemics endangering large swaths of the population. A recent story from the World Economic Forum in Davos, Switzerland stated that a theoretical future potential pathogen, dubbed Disease X, could be 20 times more deadly than COVID-19.
Disruptive technologies, such as artificial intelligence (AI) has already been used to plant conspiracy theories to insert falsehoods into social, political, and scientific interaction world-wide. For example, false claims about vaccines and untruthful side effects such as autism in children. Eradicated diseases such as measles in the last couple of years have shown a resurgence because of these falsehoods.

I strongly recommend checking out both the video and the text summary describing the dangers and challenges ahead.

Think of the Chinese characters for “crisis”: danger and opportunity.

(Yeah, I know that translation is not accurate, but the phrase truly represents the current world situation.)

A Picture Paints 1,000 Words

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Wednesday December 06, 2023 · 3:36 PM PST

2023/12/06 · 15:36

From NCEP Climate Forecast System analyses. Posted on Climate Reanalyzer (ClimateReanayzer.org), Climate Change Institute, University of Maine. The heavy dotted line represents the 1979-2000 global mean temperature, and the dashed lines above and below the mean represent represent 2 standard deviations above and below the mean. For a statistically stationary surface temperature, about 90% of the data lie between these two curves, and there is only a 5% chance temperatures will

It’s been quite awhile since I’ve done a climate diary. We’ve heard plenty of news stories addressing warming-related flooding, heat waves, and drought, and the impacts and future implications of these events, so for the holiday season I thought I’d provide an overview of the current state of the climate. I see global sea ice as a good way to examine

I hadn’t checked the daily mean global surface temperature graphic on University of Maine’s Climate Reanalyzer web page for awhile, and when I did on this past Monday morning, the banner graphic is what I found. The accompanying caption explains the statistical information for the 44-year record.

Mean Global Surface Temperature

On 3 December, the mean global surface temperature was 14.0^oC, 1.3^oC (2.3^oF) above normal and clearly the warmest on record. The data go back to 1979, the beginning of the satellite data record. Each year from 1979 to 2021 is represented by a gray line, while 2023 is shown in bold black and 2022 in orange. You’ll also notice that just about every day since the end of May has been the warmest in the 1979-2023 climate record. It’s also obvious that 2023 will be the warmest year on record, as has been reported recently in the media.

Spatial Distribution of Temperature Anomalies for 3 December 2023

Global distribution of mean surface temperature anomalies for 3 December 2023 (^oC).

What did the daily surface temperature anomalies look like over the globe? This graphic tells the story; temperatures in broad swaths of the world were above normal, especially in the Arctics, where anomalies were are large as +20^oC (+36^oF). The Arctic has seen the largest amplification of global warming because of reduced reflection of solar radiation by snow and ice.

The amplifying El Niño is reflected in the above normal surface temperatures across the eastern equatorial Pacific (left center, east of South America).

What’s Going On With the Arctic Sea Ice

…. and does it reflect (pun intended) those warm Arctic surface temperatures? The daily mean sea ice extent (the surface area covered by 15% or more ice) shows that after a minimum at about 4.3 million km², this year’s Arctic sea ice increased more quickly than normal until mid-November. Subsequently, there was an abrupt (though brief) slowdown and a slow recovery (blue line) to early December. In context, the last two calendar years (2022 in dark blue/black), sea ice extent never exceeded the lowest 10% of 1981-2010 values.

Statistics for the annual cycle of Arctic sea ice over the 1981-2010 period, with 2012, 2022, and 2023 annual cycles added. The heavy gray line is the median extent for the period, the dark gray shading surrounding the median represents the middle two quartiles (25-75%) of sea ice extent, and the light gray shading above and below the median indicates the 10-90% range. From the National Snow and Ice Data Center, Boulder CO.

That dashed red line, by the way? That denotes 2012, the year in which Arctic Sea Ice minimum was the lowest on record.

The 4 december 2023 ‘snapshot’

We show the distribution of Arctic sea ice for 4 December below. The shading from dark blue to white indicate sea ice concentrations over the region (represented by the color bar at right), and the orange contours show the median sea ice concentrations over the 1981-2010 period.

Graphic showing fractional sea ice extent for the Arctic region for 4 December 2023. The solid orange line denotes the median extent from the 1981-2010 period. From the National Snow and Ice Data Center, Boulder CO.

Virtually everywhere, sea ice extent is below the 1981-2010 median, except for the Fram Strait and southward (east of Greenland), where sea ice extent is near normal.

What About the Antarctic?

In late austral summer 2022 (red dashed line), the Antarctic experienced its record lowest sea ice extent. It came as a bit of a shock when 2023 (blue solid line) beat that record by over 100,000 km², followed by a winter with a record low maximum sea ice extent. Ice melt since that time started slower than normal, but increased to near normal in mid-November and to above normal in early December.

Statistics for the annual cycle of Antarctic sea ice over the 1981-2010 period, with 2022 and 2023 annual cycles added. The heavy gray line is the median extent for the period, the dark gray shading surrounding the median represents the middle two quartiles (25-75%) of sea ice extent, and the light gray shading above and below the median indicates the 10-90% range. From the National Snow and Ice Data Center, Boulder CO.

Below we have the sea ice concentration in the Antarctic as of 4 December. Large areas normally ice covered (orange contour) show open ocean, particularly either side of the Greenwich meridian (0^o) north of East Antarctica.

So, Where Are We and Why?

editorial: a history of intentional inaction

What we see here is the result of decades of inaction, in service to the oil/gas/coal industries who benefit from the status quo. These same industries’ research in the 60s predicted the outlines of where we are now. As the climate and other environmental consequences of dominance in the economy of carbon energy usage became clearer in the 70s and 80s, an increasing number of politicians were bought off by energy industry lobbyists and hefty campaign contributions. Remember the solar panels placed on the White House by Pres. Jimmy Carter in 1979? They were taken down in 1986 for roof repairs and never replaced by Ronald “Government Is the Problem” Reagan. So were the tax incentives and research into alternative energy which were to make us “oil independent” by 2000, which expired at about the same time. There’s much that can be said with respect to the time after the 1986 decisions, but I think we all know the basic outline: the freedom to make as much money as possible is far more important than the common good, which is just communism by another name </s>.

United Nations efforts over the last couple of decades, based on scientific reports on the state of the global climate issued every 5 years or so, have looked promising with all their (toothless) emission reduction targets. The current effort, COP28, hosted by the United Arab Emirates, has been a mixed bag as I understand it, and has noted that past promises have largely not been kept. That said, there is mounting pressure for commitments from participating countries to put a date certain on ending the use of carbon-based energy sources, and a growing sense of panic as the world looks more certain to pass that critical 1.5^oC threshold. Based on past “results”, it’s a little difficult to believe that there is the political will (or even the technological capability) to prevent crossing the threshold.

I’m often called “Debbie Downer” (the Sat. Night Live character), and it’s for a reason: I have a dim view of the motivations of the powers that be (see my comment above about “the common good”), wherever the source of their power may reside.

Yes, this graphic is in the public domain!

Thus ends my current foray into the climate situation. I’ve found it helpful to retreat from current events (political and climate!) to keep my sanity. Be well!

COVID isn't over

billlaurelMD

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Thursday August 03, 2023 · 7:32 AM PDT

2023/08/03 · 07:32

8/3/23: My COVID test results on top, husband's results on bottom. — COVID test results from 8/3/23 for me (top) and my husband (bottom), While the test line is faint, it still indicates a positive result. No, COVID isn't over, even though you're hearing nothing about it in the media.

Well, it happened again a year later. My husband (who is on dialysis and immune suppressants for another condition) and I took a trip to Atlanta to attend the annual convention for the National Association of Black and White Men Together (NABWMT). It’s something we’ve done since 1999 when it was held in Philadelphia. Last year we both got sick a day after coming back from the NABWMT convention held in Minneapolis (during the omicron COVID wave). I recovered from what felt like a bad cold within a week, but he wound up in the hospital for 10 days with what turned into pneumonia. Not fun, but he recovered. We were and are both fully vaccinated.

This time we did our best to wear masks in enclosed situations, except when we were in event venues, but I guess not enough to prevent infection for him. The difference between being immune-suppressed or not is showing up clearly in our situation. We don’t want to travel and have to wear a mask all the time, but it looks like that may be necessary for the duration, as hubby will be on immune suppressants for the rest of his life if he gets a kidney transplant.

Sigh.

I'm Just Going to Leave This Right Here

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Saturday May 20, 2023 · 7:32 AM PDT

2023/05/20 · 07:32

The altered sign bearing the anti-gay message in Orlando FL. – Photo: FOX35

The extreme right has the oddest way of deciding what’s in its own interests. What could that interest in altering a warning sign for road construction to a hate message to kill all of a specific minority? I’d love to hear your opinions on this, so I close with a poll.

Poll

229 votes Show Results

What particular right-wing interest is served by altering a construction sign to a "Kill All Gays" message?

229 votes Vote Now!

What particular right-wing interest is served by altering a construction sign to a "Kill All Gays" message?

Own the Libs

19 votes

Make America Great Again (a.k.a. MAGA)

1 vote

Please their dear leader DeSantis

4 votes

Show their righteous Godliness

9 votes

Show their fear of "teh gay"

6 votes

All of the above

190 votes

Climate Brief: More on Permafrost

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Friday April 01, 2022 · 12:19 PM PDT

2022/04/01 · 12:19

Using a motor pump and sprinklers, researchers of the Plant Ecology & Nature Management group simulated the effect of extreme summer rains on the Siberian tundra ecosystem. Source: Wageningen University, Netherlands

Introduction: The problem with methane

Some stories have come out recently about the melting of permafrost in the Arctic. Of course, one reason we’re worried about thawing permafrost is that the process releases methane into the atmosphere. I’ve written about methane previously, but here’s a summary of the relative impact of methane versus CO₂ as a greenhouse gas.

For an equivalent amount of CO₂, methane immediately traps at least 100 times as much as CO₂. But the methane starts to break down and leave the atmosphere relatively quickly. As more time goes by, and as more of that original ton of methane disappears, the steady warming effect of the CO₂ slowly closes the gap. Over 20 years, the methane would trap about 80 times as much heat as the CO₂. Over 100 years, that original ton of methane would trap about 25 times as much heat as the ton of CO₂.

The upshot is, any increase in methane emissions is a problem. In the next decade or so, an important way to keep the global mean temperature increase at or below 1.5^oC is to effectively address methane emissions. Without such efforts, it will be difficult to impossible to meet that goal.

Global Warming and Positive Feedbacks

There have been demonstrated plenty of what are called positive feedbacks in the climate system that exacerbate global warming. Generally, a positive feedback is the amplification of one phenomenon by another phenomenon caused by the first one. Examples in global warming include

The positive feedback from snowpack laying for less time in the cold season
The positive feedback from increased evaporation and water vapor content in the atmosphere as the atmosphere warms.
- Water vapor is an effective greenhouse gas, so the increase in temperature is reinforced by the increased water vapor, and the resulting warming further increases atmospheric water vapor.

We already are seeing increases in methane emissions from the Arctic, as discussed in previous Climate Brief diaries. Here’s a list of some of them going back to last summer:

Arctic Precipitation and Global Warming

Climate models forced by increased greenhouse gas concentrations have consistently shown that precipitation will increase in the Arctic as a result of greater amounts of water vapor resulting from increased temperatures. Recent Climate Model Intercomparison Project (CMIP) experiments with the newest climate models (CMIP6) increase Arctic precipitation even more than the previous set (CMIP5) ...

...due to greater global warming and poleward moisture transport, greater Arctic amplification and sea-ice loss and increased sensitivity of precipitation to Arctic warming.

Nature Communications, November 2021

Causes of these results are consistent with global warming physics and dynamics. Additionally, the trends noted here are consistent with what has been observed, and what retrospective runs with the CMIP5 and 6 models have shown, from 1980 to 2005. Note that model similarity to observations is a prerequisite for their use in climate projections.

We show the increase in Arctic rainfall as a fraction of total precipitation in each season for the CMIP5 versus CMIP6 by the year 2100 in the table below. This information is from the same article quoted above.

percent increase in RAINFALL fraction of TOTAL PRECIPITATION BY 2100
Experiments	CMIP5 (OLD)	CMIP6 (New)
winter	260	422
spring	141	261
Summer	51	71
Fall	192	268

So what does this mean in terms of permafrost melt?

Increased Rainfall vs Snowfall Melts Permafrost More Quickly

The banner graphic to this diary shows an experiment being run by the Wageningen University (Netherlands) where a wet summer season was simulated by irrigating the permafrost soil with water. What would be the effect of such an experimental simulation?

The scientists expected to see some increase in permafrost melting and some accompanying effects, that would end once the next cold season arrived. Indeed, there was a 35% increase in melt compared to permafrost that wasn’t so treated. However, the effect of an extremely wet summer lasted for several years; even two years after the sprinkler test, the permafrost under the irrigated sites was still thawing faster. This effect was enhanced further during periods of combined heavy rainfall and high air temperatures.

Conclusions

An author of the study put the conclusions quite succinctly:

“If we only take warmer temperatures into account, we will underestimate how much permafrost is thawing as a result of climate change, and how much extra CO₂ and methane is being released …. But it is difficult to realistically represent the effect of such precipitation extremes on permafrost thaw and greenhouse gas emissions in climate models.

Scientists working on the global warming problem could underestimate future greenhouse gas emissions caused by permafrost thaw, which in turn could render the 1.5-2^oC of global warming under possibly greenhouse gas reduction scenarios too optimistic.

Plans are to address regional variations in sensitivity of permafrost to rain, to help make more reliable estimates of future permafrost thaw.

Climate Brief: Vignettes from the front lines - Amazon rain forest

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Monday March 21, 2022 · 6:39 PM PDT

2022/03/21 · 18:39

From the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. This is the state of Rondonia, and what was a remote part of the Amazon rain forest. More images from MODIS in the area bounded by the red rectangle will be shown below. Source: NASA Earth Observatory, World of Change (https://earthobservatory.nasa.gov/world-of-change), taken August 2016.

Editor’s Note: While climate is the focus of this diary, the impacts of deforestation and ecosystem destruction on the people of the forest and their livelihood are all important.

Introduction: Deforestation of the Amazon from land use

Deforestation of the Amazon River basin has been going on since the 1970s, to clear land for agriculture and cattle ranching to supply beef to, ultimately, the world. And the local inhabitants have to be fed as well. From 1961 to 2017, the population of Brazil increased from about 80 to about 205 million people, a 156% increase, as shown in the graphic below.

Brazilian population from 1961 through 2017.

The pace of deforestation rapidly increased as first the arable grassland in southernmost Brazil and later, the Cerrado savanna ringing the Brazilian rain forest. were consumed by maize, cattle and, later, soybean production. The region became an important source for strong, lightweight wood like balsa as well. The amount of land, in hectares (ha), devoted to agricultural endeavors is shown in the graphics below.

Brazilian land devoted to maize production from 1961-2017, in ha. Increase over the period is about 140% to about 1,700,000 ha (100 he = one km²).

Brazilian land devoted to cattle production from 1961-2017, in ha. Increase over the period is about 280% to over 2,100,000 ha.

Brazilian land devoted to soybean production from 1961-2017, in ha. Soy production didn’t start until after the beginning of the period, but has increased to about 3,400,000 ha by 2017.

The bar graphic below shows the amount of rain forest lost to cultivation and cattle ranching from 1988 through 2018 in square kilometers (km²). Note that the peak near the center of the time series in 2004 corresponding to peaks in soy and cattle production. Also note the slowing of deforestation after 2004, as a result of pressure from world conservationists and the indigenous peoples of the Amazon rain forest. This period ended with the election of Jair Bolsonaro, a right-wing populist modeled after Donald Trump and other authoritarian leaders. Since his election, deforestation has been increasing at rapid rates, with deforested land area records being set for the last four months (11/21, 12/21, 1/22, 2/22). These records were set during what is usually a lull in forest removal; the Amazon rainy season.

Loss of Amazonian rain forest from 1988 through 2018 in square kilometers (km²). One km² is equal to 100 ha.

A Rain Forest Deforestation Example from the State of Rondonia, Brazil

The banner graphic for this post is a satellite view of Rondonia state in Brazil, taken in August 2016 by the NASA TERRA satellite, using the Moderate Resolution Imaging Spectrometer (MODIS). The area in the red rectangle from that graphic are shown next in a series, to show the evolution of deforestation from 2000 to 2005 to 2012.

MODIS imagery from July 2000 from the area enclosed by the red square in the banner graphic. This image is annotated with circles enclosing areas to watch for over the period. Source: NOAA Earth Observatory.

Compare the graphic above with the next one from 2005. Large areas to the upper left and lower center of the 2000 graphic have been developed with roads and clearings, in preparation for farming. Other areas toward the Buritis town center (middle right) have been further cleared.

Same as previous graphic, but for July 2005.

Areas around some 2005 cleared roads had more trees cleared by 2012, but new development is not as extensive.

Same as previous graphic, but for July 2012.

As stated above, forestation once again increased in the last several years as ways were found to get around forest preservation law, and after the 2018 election of Jair Bolsonaro to the Brazilian presidency.

Bolsonaro and Accelerated Deforestation

This video tweet from Greenpeace gives a good description of what has happened in the Amazon rain forest since Bolsonaro took office in January 2019.

Since Bolsonaro took office, deforestation in the Amazon has skyrocketed. A new set of bills proposed in the Brazilian Congress would enable further destruction that the forest cannot afford. We must fight for the Amazon, Indigenous Peoples rights, and for the climate. pic.twitter.com/IjuUg1VaHQ
— Greenpeace (@Greenpeace) March 11, 2022

There are new laws being considered in the Brazilian Congress, prominent among them “The Land Grabbers’ Bill”, which will allow land barons and corporations to use methods of deforestation that had been made illegal under previous land reforms intending to protect the Amazon. This land grab ignores the rights of the indigenous peoples of the area, and will accelerate the decline of the rain forest into single crop agriculture, and after the limited productivity of the soil is used up, range land and savanna.

Climate Change and Deforestation: Drying of the Amazon Basin

Vegetation Is a Moisture Source for 50% of Amazon Precipitation

In general, moisture depends on two sources, soil moisture and water vapor converging into a region by the general atmospheric circulation. Their relative importance varies from place to place on the globe. There are areas of the world that significantly depend on the “exhaling” or evapotranspiration of local vegetation to provide moisture for precipitation. Interestingly, the U.S. Great Plains has been shown, using climate models, to be one of them. But another that has implications both locally and far afield of it is the Amazon rain forest, both because of its vastness and its location straddling the equator.

As things stand, local vegetation is responsible for about half of the precipitation in the Amazon River Basin. It’s been shown in observations that the rainy season initiates before the ocean air reaches the area, through thunderstorms fed by moisture from the local vegetation. Only later does moist ocean air begin to travel inland through the Amazon basin with the onset of the South American monsoon, further augmenting rainy season precipitation. The data suggest that deforestation has delayed the onset of the Amazon rainy season about one month since the 1970s, when deforestation of the Amazon began.

Tropical Ocean Response to Greenhouse Gases Will Dry out the Amazon

But another problem is sea surface temperatures (SSTs). Both the tropical Atlantic and the tropical eastern Pacific are projected to warm up about 2^oF from their current levels in climate model projections forced with increasing greenhouse gas concentrations. Additionally, more frequent El Niño events in the Pacific are suggested by climate models. In the current climate, an anomalously warm tropical Atlantic and the El Niño in the tropical eastern Pacific are observed to suppress precipitation in the Amazon. The trends in tropical ocean SSTs forced by global warming will serve to compound the drying of the Amazon from deforestation.

A Tipping Point for the Amazon Rain Forest?

There were several articles published recently regarding the possibility that conditions conducive to resilience of the Amazon rain forecast may be approaching a tipping point beyond which recovery will not be possible without massive amounts of human help. Some of the reasons are discussed next.

Resilience of the Amazon Rain Forest to Environmental Stress Is Decreasing

By using satellite imagery over several decades, scientists can assess how well the rain forest can bounce back from stresses like deforestation, drought, and anomalous warmth. According to a study published in the journal Nature Climate Change, more than 75 percent of the rain forest is losing its ability to bounce back (“resilience”). The vegetation is drier and takes longer to regenerate after a drought, even in the most densely forested areas.

Reduction in resilience could be an early warning sign that the Amazon is nearing its “tipping point,” according to the study’s authors. Between humans destroying large swaths of the forest and the change brought about by that and exacerbated by global warming, we may witness a sudden dieback of trees requiring a substantial wet season and their replacement with trees that are more able to adjust to drought and heat, i.e. savanna vegetation. This transition has already been observed in a study of 100 sites in the Amazon over the period from 2016-2019. The same study has found that the rain forest tree dieback has not been sufficiently compensated by the increase in drought-resistant trees.

What Will Be Lost Without the Amazon Rain Forest

Research of the combined impacts of deforestation and global warming on the Amazon suggest that over half of the rain forest could transition into savanna in mere decades. This in turn would result in reduced biodiversity and shifting regional weather patterns.

On a larger scale, consider that the Amazon has been one of Earth’s most important “carbon sinks,” pulling billions of tons of carbon dioxide from the air and storing it in vegetation. Current data has suggested that the Amazon has now become a carbon source, to the tune of one billion tons of CO₂ per year. What are the sources for this CO2?

Burning to clear land for agriculture and range land
The loss of vegetation available to absorb CO₂, and
The byproducts of producing cattle for beef, including the cattle itself.

The loss of the Amazon would put limiting temperature rise to 1.5 degrees Celsius (2.7 degrees Fahrenheit) out of reach.

It’s not clear what the tipping point is; it’s possible we are already there if the decline in resilience has reached the point where the trees of the Amazon rain forest die whenever there is a drought, with or without curtailment of deforestation for whatever purpose.

Conclusions

The Amazon rain forest is an important component of the Earth system, providing a important buffer to rapid climate change, because:

It is a vital sink for the Earth system’s carbon cycle, essential to the mitigation of greenhouse gas emissions.
- If the Amazon rain forest degrades into savanna, it will become a source for CO₂ rather a sink, which will increase the pace of global warming.
It has historically been self-sustaining, with moisture from its vegetation providing half of its annual precipitation.
- Deforestation disrupts this cycle and delays the rainy season, because:
  - Fewer trees are available to draw moisture from the soil into the atmosphere to be recycled as precipitation.
Its degradation beyond a “tipping point” will result in the permanent loss of this vital resource.
- Loss of rain forest resilience suggests that this tipping point is imminent, or even already exceeded.
- Such a result will make it all but impossible to keep the mean annual Earth temperature from increasing only 1.5^oC above the 20th century value.

Climate Brief: Vignettes from the front lines - the Arctic sea ice maximum

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Friday March 11, 2022 · 1:06 PM PST

2022/03/11 · 13:06

no image description available — Time series of area of polar ocean with at least 15% sea ice coverage, 1 December through 30 April. The current season 2021-22 is in light blue and shown through 8 March 2022. Source: The National Snow and Ice Data Center, Univ of Colorado -- Boulder.

Introduction: A quick overview of the last 30 years

If you look back at my story record from say 2010 through 2012, you’ll find some diary entries from 2010 through 2012 titled “News From the Arctic: ...”. For awhile I wrote them weekly, but I slowed over time and then stopped for good in May 2012. For this week’s Climate Brief, I thought it would be interesting to look at Arctic sea ice as we approach the Arctic sea ice maximum, which typically occurs any time from the last few days of February to as late as the 2^nd of April (in 2010).

A note on how sea ice extent is measured

Satellite observations are used to determine sea ice extent. If a water “pixel” (~3x3 km) has a 15% or higher sea ice coverage, it is considered to be covered with ice. The 15% threshold is used to reduce the large variability found at low percentage coverage. that result from day-to-day weather variations.

I used the banner graphic to display the time series of the last several months’ Arctic sea ice extent (from 1 December 2021 through 9 March 2022, in light blue) from the National Snow and Ice Data Center (NSIDC), located at the University of Colorado — Boulder. Other data are plotted through April 30:

The minimum sea ice extent year (2011-12) is in dark green dash for comparison.
The heavy gray line is the median value (i.e. in the exact middle) for Arctic sea ice extent from 1981-2010
The dark shading represents the “interquartile range (from 25% to 75%)
The wider, lighter shading is the interdecile range (10% to 90%).

There has been no year since 2001 with maximum sea ice extent as high as the 1981-2010 median, with every year since 2006 in the bottom 10% of the 1981-2010 range.

Next, here’s a plot of the 1981-2010 median Arctic sea ice extent (heavy gray line) with the 1979-1990 (gold), 1991-2000 (light green), 2001-2010 (black), and 2011-2020 (blue) averages.

Decadal average Arctic sea ice extent for 1979-1990 (gold), 1991-2000 (light green), 2001-2010 (black), and 2011-2020 (blue). Source: NSIDC, Univ of Colorado -- Boulder.

You can easily see the rapid decrease in warm season Arctic sea ice minima, especially over the latest two decades. In 1979-90, mean sea ice minimum averaged about 7,000,000 km²; while the following three decades averaged about 6.5 million, 5.5 million, and 4.4 million km², respectively. The final 2011-2020 decade includes the record low minimum sea ice coverage of about 3.4 million km², which occurred in August 2012, when an abnormally strong cyclone entered the Arctic Ocean basin and caused massive disruption of the sea ice in an area where it was already unusually thin.

The Road to This Year’s Arctic Sea Ice Maximum

The 2021-22 sea ice freeze season started from the highest sea ice minimum since 2009. The summer season, though 1-2^oC warmer than normal over much of the Arctic Ocean basin, was also characterized by lower pressure and more cloud than normal, which limited sunlight available for absorption by exposed water. Because of wind anomalies consistent with the lower than normal pressure, circulating sea ice spread out more than in a typical summer. This led to larger areal coverage of 15% or more sea ice (but not more overall sea ice) than in recent years.

I’ve annotated a graphic from NSIDC showing annual or season to date Arctic sea ice extents for 2021 and 2022. For comparison, I’ve included the ±2 standard deviation from the 1981 to 2010 median, and the decadal averages shown before (same color scheme).

Arctic sea ice extent for 2021 (very dark green) and through 9 March 2022 (blue) from the NSIDC. Shading represents 2.5-97.5% range of the extent distribution from 1981 through 2010. Decadal averages for 1979-90 (gold), 1991-2000 (yellow), 2001-10 (black), and 2011-20 (light blue) are also shown. Source: NSIDC, Univ of Colorado -- Boulder. Annotated by author.

The 2021-22 Arctic sea ice season began with a minimum higher than any since 2014, but on a date only two days later than the average of 14 September. October found faster growing sea ice than in recent years because of favorable conditions on the Siberian side of the Arctic Ocean. The faster than normal increase in sea ice area continued in November, and by the end of the month was just above the lowest 10% values over the satellite observation period for the first time since 2017. This was in spite of essentially no sea ice in the whole of Hudson Bay.

In December, colder than normal weather in central Canada froze over the entire Hudson Bay, bringing it to near-average ice cover. And while well-below normal, Arctic sea ice extent was the highest since 2014. By the end of January, sea ice extent was ranked higher than it had been since 2009. February saw a slowing of sea ice growth leaving area coverage at the lowest 10% of the recorded values for any given day. Finally, as of yesterday, 9 March, sea ice extent is actually about 100,000 km² lower than it was at the end of February which, if trends continue, would mark one of the earliest maxima in the satellite record.

Can We Tell What the Melt Season Will Bring?

To do any predicting for the melt season, we need more than just sea ice coverage. We need to know the sea ice volume: the area times the ice thickness. The latter is often difficult to “get at” from observations, though innovations in satellite data processing, as in many other Earth observational methods, allow for decent estimates of sea ice thickness when combined with sea ice volume models, discussed next.

Sea ice volume models

Sea ice volume can be obtained from satellite estimates of sea ice thickness, Naval submarines, moorings from ongoing field campaigns out on the ice, etc.). These are not continuous given current capabilities, so a sea ice volume is used to make the data continuous and consistent over time. The Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) is just such a numerical model, developed by the Polar Science Center in association with the University of Washington. with components for sea ice and ocean, and a data assimilation system to constrain the ice volume to best fit the analysed weather conditions, like wind, surface air temperature, and cloudiness (for incoming solar and outgoing terrestrial (long wave) radiation). The necessary sea ice concentration information from NSIDC comes from satellite data and sea surface temperature (SST) data from the NOAA Ocean Prediction Center are used for ice-free areas. The wind, surface air temperature, and cloud cover (to compute solar and long wave radiation) are specified from the joint National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis. The pan-Arctic ocean model is provided input data from a global ocean model at its open boundaries located at 45^oN.

History of Sea Ice Volume

Three graphics tell the story about sea ice volume during the satellite data record starting in 1979 … decline. Satellite data on sea ice drift can be used to calculate the age of sea ice. First year ice was born in the most current freeze-up season, with any ice that survives a melt season denoted as multiyear ice, whose age is the number of melt seasons it has survived, The age of sea ice can be used as a proxy for sea ice thickness. The contrast between 1984 and 2021 is striking! In 1985, more than half of the sea ice was more than four years old, while in 2021, almost all of it has vanished, with most of the ice from just the previous freeze-up.

Top: Areal extent of Arctic sea ice age at the 1984 sea ice minimum versus the 2021 sea ice minimum. Sea ice age is as indicated by the color legend at the bottom of each map.
Bottom: Time series of Arctic sea ice age at sea ice minima from 1984 to present. Colors are sea ice age using the color legend for the top graphics. Source: NOAA Arctic Report Card: Update for 2021.

How does this translate to volume? Here we’ll use the PIOMAS model results described previously. April is used for the volume maxima and September for the volume minimum, with data plotted from 1979 — 2021, The right edge of the graphic which shows 2021 is, unfortunately, cut off.

Time series of April and September Arctic sea ice volume from 1979 through 2021. Trend lines are indicated and identified, with dashed lines showing ±1 quartile (25% either side of mean) and the dotted lines showing the 10th and 90th percentiles. Source: Polar Science Center, University of Washington.

Again, the trends are clear, with decreases of 2.6±1 km³/decade for volume maxima and 3.2±1 km³/decade for volume maxima. In the last decade (2012-21) the pattern seems to have flattened out somewhat, especially for the sea ice volume minimum. Note the record low volume for maximum ice was recorded in April 2017.

Forecasts for September 2021 Sea Ice Minimum

Yes, there is a forecast contest for best prediction of Arctic sea ice minimum extent run by an organization called the Arctic Sea Ice Prediction Network, called the Sea Ice Outlook. In essence it's an experiment to learn the economic value of these sea ice outlooks and to investigate the relative importance of each component that determines the evolution of sea ice during the melt season. Currently the experiment is in the last year of its second phase; the first being run from 2014-17.

There were 160 forecasts made for the 2021 sea ice minimum. Each participant, usually a full organization affiliated with either an educational or private sector institution, sent in forecasts in June, July, August, and early September for the September 2021 minimum, using different methods. The results are shown below, with individual forecasts shown as horizontal bars, the median of all forecasts as a vertical dashed line, the 2020 observed minimum as a vertical blue line, and the verification for 2021 as a heavy black line.

June, July, August, and September 2021 Outlook contributions for Arctic sea ice extent, with median (blue dashed) line, September 2020 observed extent from the NSIDC Sea Ice Index (gray line), and September 2021 (4.92 million square kilometers) observed extent from Sea Ice Index (black line). Source: Arctic Research Consortium of the U.S. (ARCUS), Sea Ice Prediction Network.

Dependencies on weather

The forecasts provided by the contest participants woefully low balled the 2021 verification. As you may recall, when I talked about the 2021 summer season, note was made of the high amount of cloudiness (thus low solar radiation in, and low infrared radiation out) and the wind-driven dispersion of the ice so that a wider area met the criterion of 15% ice cover than might be expected otherwise. So one could say that these forecasters were heavily influence by last summer’s minimum (what one could call using “persistence” in your forecast), rather than looking at what was actually persisting … the months-long weather pattern unfavorable for melting more ice.

Conclusions

While we cannot predict how much or how little sea ice will exist at a given maximum or minimum for any year, it’s unequivocal that the Earth is losing its sea ice in the Arctic. Interestingly, the Antarctic melt season (remember that southern hemisphere seasons are reversed from ours in the north) concluded with a record minimum sea ice extent in late February 2021.

Arctic/Antarctic sea ice and snow act as a sort of air conditioner that tempers the global mean temperature. Unfortunately, it also is highly sensitive to, and is a major drive of, global warming. As snow and ice melt, more solar radiation is absorbed rather than reflected. Ocean water goes from reflecting ~65% of incoming solar radiation when covered by ice and snow, to only about 8%, and land snow/ice from about 70-80% to 15-20%. This is why polar regions are showing a larger temperature response to greenhouse gas emissions than anywhere else in the world.

The result has been loss of permafrost, arctic habitats, native culture and livelihood, and so on. One of the most depressing emblems of arctic warming and the loss of sea ice is the polar bear. I’m sure you’re all familiar with that picture that makes you want to bawl your eyes out, so I won’t torture myself (or DKos readers) with that image. Let’s suffice it to say that things aren’t looking too good.

Comments are welcome, please, including corrections of anything I may have misstated or omitted.

Climate Briefs: Vignettes from the Front Lines - Mississippi Delta

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Saturday March 05, 2022 · 12:19 PM PST

2022/03/05 · 12:19

From 1922 to 2014: The vanishing wetlands

The Mississippi Delta has been a story of disappearance. In 1922, you can see the 1922 coastline in the banner graphic to this entry outlined in grey. This was before development of the wetlands and the coastline; before the Army Corps of Engineers built their levee system after the devastating 1927 floods that extended from just south of where the Ohio and Mississippi Rivers merge to the Gulf of Mexico; before the petrochemical industry lined up refineries between Baton Rouge and New Orleans, because land was cheap and 49.1% of the residence were black and probably wouldn’t notice; and before the same industry began siphoning off oil from beneath the wetlands starting in 1926. By 1990, there were 500 or more oil and natural gas wells in the wetlands south of the Mississippi River.

These human activities resulted in 1800 or so square miles of wetland sinking beneath the encroaching ocean water between 1922 and 2014. In my banner graphic, you can see the extent of these lost wetlands in dark blue between the 1922 shoreline and the colors representing the 2014 land surface. The red areas within the wetlands represent expected losses of land from 2014 through 2054, while the green areas represent gains in land during the same period.

The View from Buras, LA

At one time, the view from Buras, LA looking to the south was rich with wetlands supporting cypress stands, marshes, and low ridges that acted to separate bodies of water into bayous and bays. Fishing camps were set up through the area for sportsmen to catch speckled trout, flounder and red snapper. The marshes were even fresh enough to attract wintering ducks. The bays produced large catches of salty oysters and large shrimp for restaurants in the French Quarter to make into tasty dishes.

The Mississippi Delta in Buras, LA and vicinity, 1956-1971. Buras is the built-up area on the west bank of the Mississippi; levees protect it on all sides, isolating the wetlands from the River itself. Courtesy: NASA/USGS.

Even before the 2010s, the marshes, cypress swamps and ridges separating the bayous and bays had washed away, leaving one large, open body of water. All the small bodies of water between Buras and the Gulf of Mexico were removed from nautical maps by NOAA in 2013. You can see where they once were (red dots annotated with former names) in the map below from 2009.

The Mississippi Delta in Buras, LA and vicinity, from 2009 forward. Buras is the built-up area on the west bank of the Mississippi; levees protect it on all sides, isolating the wetlands from the River itself. Note the amount of wetlands essentially converted to the Gulf of Mexico over the ~50-year period. Courtesy: NASA/USGS.

Areas of Wetland Growth: The Atchafalaya River and Wax Lake Canal Deltas

Yes, there are areas where wetlands are actually building, but first, a few quick words on how deltas are formed. Silt to build and maintain wetlands is brought from a river watershed to its delta and deposited, especially during flood events. What has gone wrong in the Mississippi delta is the establishment of flood control. Levees and canals have cut existing wetlands off from the river, causing them to sink because they are starved for silt. The Mississippi delta is sinking at one of the fastest rates of any coastal landscape on the planet.

One area going against the trend, however, is the Atchafalaya River delta, about 70 miles west of the Mississippi River delta. Here, unencumbered by levees, the Atchafalaya — which flows off the Mississippi north of Baton Rouge — has been building two new deltas for decades, as can be seen in the following graphic.

An area of the Louisiana Gulf coast offers hope for Louisianans dependent on the Mississippi delta wetlands for a living. Within the box are areas where wetland area growth is demonstrably possible because the rivers involved are not disconnected by levees: on the left is the Wax Lake Delta and on the right is the Atchafalaya River delta. From NASA/USGS LandSat, via ArsTechnica.

One of them, the Wax Lake Outlet delta, is the result of the 1942 dredging of a new canal above Morgan City, LA to mitigate flooding threats to that city. This canal removes 30 percent of the water from the Atchafalaya and shunts it straight to the Gulf, without levees and with plenty of silt.

These building deltas gave Louisianans an idea. So to save the wetlands of the Mississippi Delta, the Federal Government and the State of Louisiana formed the Coastal Protection and Restoration Authority (CPRA) in 2006. Based on the evidence from the Atchafalaya, Louisiana’s Coastal Protection and Restoration Authority (CPRA) developed a 50-year plan to reconnect the sediment-rich Mississippi to the sinking delta basins that were cut off by levees in the 1930s and deprived of silt by gas and oil company canals starting in the 1940s. Details of this plan can be seen on CPRA+’s webpage here. I’m not disciplined enough to explore the CPRA site fully, but suffice it to say a cursory look at projects in operation includes infrastructure repair; freshwater, marsh, ridge and barrier island restoration; marsh creation, storm resilience, and others.

These projects, and the $1+ billion per year allocated to them by federal, state and local government, could be a basis for hope. It appears that the knowledge and capability to make the necessary repairs exist, but is enough money being allocated?

CPRA Budget

Expenditures will be about $3.5 Billion for FYs 2023-25, but almost $2.5 Billion if for Deepwater Horizon remediation, which leaves about $1 billion over the period for wetland restoration and related projects. It appears that once the infrastructure is finished, which would include silt diversion, marsh restoration, and barrier island/marsh ridge buildup, the maintenance would be easier to budget. It also appears that there is a long term commitment being made to restore and protect the Mississippi delta. The question is and will always be, is it enough, and soon enough?

As Rachel Maddow always says, “Watch this space” (literally).

Climate Brief: Methane, wildfires, and drought, oh my!

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Friday February 25, 2022 · 2:51 PM PST

2022/02/25 · 14:51

A collage of potential doom. CO2 concentrations on upper left (ppm), CH4 on upper right (ppb). On lower left is a stock photo of drought and on the right one for wildfire. All images in the public domain.

Author’s note: As I write this entry, I stand united with the people of Ukraine. I'm also very concerned about this conflict becoming WWIII, all because a tyrant wants the world to bend their knees to him. This is a disturbingly familiar story, but this time with added nukes.

Climate News That Has Been Overwhelmed By Ukraine

As I sit here and begin writing this, it’s 73^oF in Laurel MD after a low of 60^oF overnight. But also, as the savvy global warming activists (should) know, what goes on from day-to-day in a small area does not inform us on whether warming is occurring on a global scale. While it is lovely here at the moment, winter storm warnings are up from Dallas-Fort Worth into the lower Ohio Valley for snow, sleet, and freezing rain.

Speaking of global warming, here is the average temperature anomalies for last month over the full globe. Interesting to note that the coldest place relative to normal was eastern North America, especially adjacent areas of Canada and the U.S, Averaged globally, the mean temperature of 53.6°F (12.0°C) was 1.60°F (0.89°C) above the 20th-century average and ranked as the sixth-warmest January in the 143-year record.

January 2022 distribution of monthly mean temperature anomalies, compared to the 1991-2020 base period. Note that these anomalies are less high than they would be if they were the difference from the 20th century mean in each longitude-latitude grid box. Source: NOAA/NCEI

Methane news

As for CH₄, we’ve covered it and its greenhouse gas impacts in earlier diaries, including from yours truly. As I mentioned in that diary, the reason CH₄ is such a concern is its potency; over 20 years, it has about 80 times the impact of CO₂. It currently is the cause of 30% of observed global warming. Finally, national energy sector CH₄ emissions, reported to the International Panel on Climate Change (IPCC), are 70% lower than measurements performed by research studies.

The rest of the information in the CH₄ section relies on the IEA’s updated Global Methane Tracker, which has been enhanced in recent years with new data sources from real-time observations from satellites, for example. Documentation of its data sources and calculation methods are found in this publication. In the graphic below, we see that from all sources, the most CH₄ emissions in 2021 came from wetland processes; followed by human activities in agriculture, carbon-based energy production, and decay of waste products. Note that the emissions breakdown among oil, gas, and coal is about even (the much smaller green part of the bar represents emissions from biofuel production).

All sources of natural and human-generated CH4 emissions for 2021 according to the IEA, in megatons. Source: IEA

Looking at just human sources, came from agriculture (42.4%), with energy from coal, oil, gas, and biofuels close behind at 37.9%.

All sources of human-caused CH4 emissions for 2021 according to the IEA, in kilotons. Source: IEA

Next we will see the importance of scientific, objective measurements of human-derived CH₄ emissions. Below, we compare what is reported by the IEA for global CH₄ emissions versus the total reported to the United Nations Framework Convention on Climate Change (UNFCCC).

global-methane-emissions-by-sector-reported-to-the-unfccc-and-estimates-from-the-iea.png — Methane broken down by type of human activity. Light blue is reported by the IEA, while dark blue is reported by member countries to the United Nations Framework Convention on Climate Change (UNFCCC). Units are in megatons. Source: IEA

Note that the IEA shows higher emissions than the total reported to the UNFCCC in every human endeavor involving the generation of methane.

And what a surprise! The biggest difference is in the energy sector, where actions to reduce emissions are resisted by energy companies, with the acquiescence and even active participation of government.

Last November at COP26, at least a glimmer of hope appeared as the Global Methane Pledge, which would reduce methane emissions 30% globally by 2030. While not binding, at least it provides a framework for a way to keep global warming to within 1.5^oC. An inducement to keeping to promised made in this agreement is that, for the first time, the Global Methane Tracker is, for the first time, able to break down emissions by country. This will allow for an independent determination of whether promises made do become promises kept.

New Assessment of Wildfire Risk Worldwide

The UN Environmental Program (UNEP) released a report on global warming and its potential impact on extreme fires in the environment.

The scientists who performed the research for the UNEP, project a global increase of extreme fires of up to 14% by 2030, 30% by the end of 2050 and 50% by 2100.

The rapid change in fire conditions seen in the last several years was seen to make the analysis necessary according to one of the lead report editors, Andrew Sullivan, who works for the Commonwealth scientific and Industrial Research Organization in Canberra, Australia. Recall that Australia has had a series of droughts and wildfires that have killed over one BILLION animals, including potentially endangered koala bears.

Over the last two years, extreme wildfires have occurred in both the Northern and Southern Hemispheres. Some have been of unprecedented size and have occurred in unexpected seasons, like the recent Marshall Fire that destroyed about 1,000 suburban homes near Boulder, Colorado in late December. Since the new year, large and intense fires have ravaged parts of Argentina and Chile, including Patagonian forests that have rarely seen large fires. Many towns and cities in this area have also seen their highest temperatures on record.

The report admits there is really no way to eliminate wildfires; indeed they are a natural part of nature’s management of the ecosystem. However, better management may help in some cases, for example in California (e.g. Paradise CA wildfire in 2020), and anywhere development bumps up against the wilderness. Needless to say, stopping and hopefully reversing global warming would be most helpful.

Drought Around the World

Drought is expected to become a problem for an increasing number of countries around the globe. At present, drought and other agriculturally impactful weather has been occurring in a number of areas. We discuss each region below. For the California drought, see my diary from last week.

Madagascar

First drought and then four tropical cyclones in a month! While the cyclones broke the drought, the damage they wrought made food insecurity for this impoverished country even worse. The drought itself was marginally attributable to global warming, but because of the susceptibility of this country to drought, almost all of the cause is considered to be natural climate variability.

Argentina/Brazil/Paraguay/Uruguay

I mentioned the wildfires in the previous section in Argentina and Paraguay. These have been accompanied by unprecedented heat and dryness in these areas as well. The area is an important area for soybean, corn, and wheat, as well as an important provider of beef.

West Africa: Northern Sahel

The northern Sahel (Burkina Faso, Mali, and Mauritania) have been suffering from both extreme drought and internal conflicts. Both are contributing to food insecurity in the area.

East Africa

In East Africa, the latest seasonal climate forecast shows an increased likelihood for a fourth consecutive poor rainfall season for MAM 2022 in the eastern Horn of Africa, northern Ethiopia, and Kenya, consistent with the current La Nina event.

Climate Brief: The Southwest US drought might now be the new normal

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Friday February 18, 2022 · 12:00 PM PST

2022/02/18 · 12:00

Note: I’ll be using California to represent Southwest drought for this blog entry.

Introduction: The current state of the California drought

Let’s start with the graphic I’ve chosen for the banner above, courtesy of the Drought Monitor maintained by U of NV Las Vegas. The shading shows the degree of soil moisture dryness, as indicated by the Intensity legend at the lower right of the diagram. Drought Impact Types are indicated by areas bounded in black lines and are labeled short-term (labeled S, up to and including 6 months. affecting agriculture and grasslands) and/or long-term (labeled L, greater than 6 months, affecting the above plus general hydrology and ecology). As of February 8, 2022, more than half of the lower 48 (CONUS) is drier than normal, with various short- and long-term impacts based on the persistence of dry conditions.

The drought in California has been ongoing, with a couple of breaks, since about 2000, with serious impacts on agriculture (S), general hydrology/water supply, and ecology, and a ramping up of forest fire size and damage (L). None of the breaks in the drought have restored long term water supplies to normal over the last 22 years.

If we use reservoir levels as a measure of long term surface and subsurface water storage overall, reservoir levels from last week tell a troubling story. After December’s record precipitation over CA, it has not rained since January 7 in northern CA, and not since January 16 in the southern portion of the state. The graphic below shows that last week’s levels were, except for three reservoirs, below normal for this time of year. Current levels are indicated by the blue shading, normal levels by green horizontal lines, and total capacity by the full rectangle (yellow and blue shading).

Major CA levels on February 9, 2022, courtesy of SFGate.com.

Most reservoirs are below their levels in 2021 on the same date as well (not shown, see story link in preceding text and figure description above).

How Did CA Get Here?

It’s not only lack of precipitation

The role of anomalous heat in development and intensification of drought cannot be overstated. As dryness increases and evaporation from soils and evapotranspiration from vegetation decreases, a larger share of incoming solar energy increases the ambient temperature. We can see both processes in the graphics of 20-month periods (Jan. through August of the following year) and 20-year centered averages for precipitation (left) and temperature (right) for the Southwest since 1895.

Records of precipitation, left, and temperature, right, in the Southwest United States since 1895. Dots show individual 20-month periods corresponding to the analysis period in the report, while the solid gray line shows the centered 20-year average. The exceptional nature of the most recent 20-month period is clear in the long-term records, as is the multi-decadal upward trend in temperature. (NOAA and Washington Post)

The striking 20-year centered average temperature increase since the late 1970s reflects both the long-term drying of the region and the impact of greenhouse gases. Also note the extreme dry departure of precipitation in the most recent 20-month period (Jan. 2020 — Aug. 2021), which was the driest over the last 126 year record. There’ll be more on the contribution of anthropogenic global warming (AGW) to the Southwestern US/California drought later, after we look at the drought forecast from now through spring of 2023.

Near-term Expectations for Precipitation and Drought

February is the climatologically wettest month in much of CA, because the storm track is furthest south. However, for years with cold equatorial eastern Pacific sea surface temperatures (the well-known La Nina) like this one, drier than normal weather is typical in winter, especially in CA.

The medium range forecast (14 days) shows 0-0.5” of precipitation over the southern half of CA, with from 0.05” to about 3” of precipitation over the northern half. In all areas this represents only from near 0% to about 50% of what should be received during the period. March is expected to have near normal precipitation over the southern 80% of the state, with above normal amounts restricted to the north.

Starting in April, California and the rest of the US west coast begins its dry season. In its most recent projection, the NOAA Climate Prediction Center (CPC) indicated a continuation of drought over CA and the rest of the Southwest through at least April 30, 2022. Also of concern is the large area of drought persistence (brown) over the Rocky Mountains, and western and southern Great Plains. This is also common when the central and eastern Pacific is in its La Nina phase. Note the expectation that drought will expand eastward and southward through April 30. None of this bodes well for winter wheat in the Southern Plains or warm season wheat further north.

Latest 3 month outlook for drought from that NOAA Climate Prediction Center issued January 31, 2022. Current drought persists and expands over much of the West and Great Plains, and expands eastward and southward.

I took a quick peek at next year’s projected CA wet season from the CPC (predictions for three month periods from OND 2020 through JFM 2023) and it holds to drier than normal weather from CA into NV, AZ, and parts of OR, UT, and ID. Needless to say, however, predictive ability does decrease over increased projection time.

Why This May Be the New Normal for CA

Research on historical droughts

A press release was issued early this week on a study published in the journal Nature: Climate Change on the 2000-2021 southwestern US drought. A study from 2020, using soil moisture proxies such as tree rings from carbon-14 dated wood, concluded that 2000-2018 was the driest 19-year period since the megadrought (i.e. a drought lasting two decades or more) of the late 1500s (1571-1593). In the earlier study’s conclusions, the authors expected that the plentiful precipitation of the 2019 water year would terminate the 2000-2018 extended drought.

However, rather than ending, the drought was further exacerbated in 2020 and the extremely dry and hot 2021 (from reconstructed data, driest since 1729). The additional two years dominated by drought resulted in the current designation of 2000-2021 as a megadrought in the most recently published 2022 study. This megadrought is the first to occur in 400 years, and represents the driest period as measured by soil moisture and their proxies over the last 1200 years.

Previous research has shown that the period from 1600 back to 800 CE was punctuated by seven megadroughts in the southwest US, one of which lasted for 30 years (1271-1300). These were caused just by natural climate variability. In contrast, the subsequent 400 years were unusual in terms of relatively stable precipitation and temperature. Based on the reconstructed record alone, the current megadrought may mark a return to an old normal. It’s also an ominous reminder that development of the Southwest was based on the continuation of what may have been an anomalous stable regime. But how much of the current situation is made worse by AGW?

Comparison of recent observed climate changes to climate models

The most recent study of Southwestern drought used models currently used for climate projections based on anthropogenic global scenarios rerun for the 1901-2021 observational period (not requiring reconstruction with proxies), but without increases to greenhouse gas concentrations. The researchers then used the difference between the two runs to estimate the AGW contribution to the 2000-2021 megadrought.

results

The first graphic used the full reconstructed soil moisture time series to compare to the current 2000-2021 megadrought, and to the 2021 extreme. See the caption for a full description.

Left: Time series of soil moisture anomalies (standard deviation) for 22 year averages (top) and yearly values (bottom). Black line is the reconstructed data from 800-1983, with grey showing the 95% confidence interval (CI) derived from the reconstructed record. Red shows observed soil moisture anomaly (1901-2021), and blue shows the contribution from AGW). The 2000-2021 (top) and 2021 (bottom) anomalies are shown by the red horizontal lines.
Right: rank of current drought severity (per the legends to the right) with and without AGW. Top shows the 22 year drought rank, and the bottom the rank for 2021 alone. Ranking is based on the full reconstructed record

The researchers estimate that about 42% of the current megadrought and 19% of last year’s even more extreme dryness appears to be attributable to AGW.

Next we have a closer look at the megadroughts of 800-1600 compared to the current one. I won’t go into an extended description of the statistical methods used to verify the significance of the results, beyond that the soil moisture deficit graphic below include plus and minus 95-percentile bounds based on drought reconstructions (shaded, with a 2.5% chance of a correct value beyond the upper or lower bound).

Left: Evolution of five worst megadroughts from start through 22 years. Legend indicates years of occurrence. The blue line shows the current drought after removing the estimated impact from AGW.
Right: Same as left but for each drought from beginning to end, with the blue line again representing the current drought without the effect of anthropogenic greenhouse gas emissions. Without AGW, the current drought would not have begun until 2007, using the definition in the article text.

Soil moisture deficits in the current drought evolved at least as quickly as in any of the droughts over the past 1200 years, and the contribution from AGW is clear.

Conclusions/Speculations

Drought has not occurred over the last four centuries to the degree or intensity in the US Southwest as in the previous 800 years.
The development of large cities and agricultural regions with high water demand in the last 100 years occurred during a long period of stable climate (both precipitation and temperature), which was able to support such development.
About 55,000,000 people live in CA, AZ, UT, and NV. The current reversion to more frequent drought, while new to the region since its development, is likely to continue, at least in part because of AGW.
While not directly discussed above, water storage in much of the region is at record low levels.
1. The Colorado River watershed supplies water for drinking and power generation for 40 million people in this region. The snow pack that provides water to the river has been running below normal during the megadrought. Reservoirs fed by the Colorado (Lake Powell and Lake Mead have been at record low levels.
2. The Sierra Nevada provides snow melt for large reservoirs and the Central Valley of CA (Sacramento and San Joaquin Rivers). The snow pack here too has been adversely affected by the megadrought. Reservoirs dependent on snowmelt are also at seriously low levels.
3. The current hydrologic infrastructure may not be sufficient for the current population, let alone any future growth.
There will have to be significant changes to the hydrologic infrastructure (adding desalinization of seawater? Diverting water from wetter regions?) and to lifestyles relative to water use (Recycling wastewater at the household level?).
Agriculture will need to convert to growing crops with less water demand than those grown presently, or to use water more efficiently.
Another more extreme alternative would be to reduce the population of the Southwest to a sustainable level based on expected water availability, which may be difficult to determine.

Climate Brief: More bad news from the Poles

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Friday December 17, 2021 · 5:00 PM PST

2021/12/17 · 17:00

Poles come from Poland. Unless they're on a rotational axis.

Introduction: The Poles and Global Warming

The Polish people have been participating for decades with other human beings, in a nefarious plot to breathe out too much CO₂. This has resulted in an increase in CO₂ concentrations from about 350 ppm in 1950 to over 420 ppm today. COP26 chose to ignore the exhalation of CO2 by Poles and other humans in its assessment of global warming, and provided no solutions to prevent a 2^oC increase in global mean temperature by 2100.

WTF?

I’ve been in a strange mood for the last couple of weeks, as you can tell from my attempt at humor here. Part of it is the time of year; I’m a bah humbug type of person who has trouble getting into the holiday spirit. The rest is feeling negative about the long term prospects for the country. To those of you who object to demonizing the Polish people with such a ridiculous smear:

I included other human beings as causing the problem, which should reduce the risk of an individual group from being harmed, and
Smears belong on bagels, not humans.

Okay, I got that out of my system. Pray for me.

The Real Introduction

The National Ocean and Atmospheric Administration of the U.S. (NOAA) issues an annual report referred to as “The Arctic Report Card”. The 2021 report card was issued yesterday, 14 December, and highlights the continued rapid change observed in real time, which has been discussed in these pages frequently during 2021, and periodically for a number of years previous to that. A convenient graphic in that report card highlights observed Arctic-wide and regional changes here.

See more information on this under the “Arctic” subheading.

While the Arctic is big in the news today, we don’t want to ignore the Antarctic. How’s this for an eye-grabbing headline? Crucial Antarctic Ice Shelf Could Fail Within 5 Years, Scientists Say.

We’ll also briefly discuss the Antarctic Ice Shelf problem at the end of this entry.

Arctic-wide Events

Much of what is in the 2021 Arctic Report Card has been reported on in Climate Brief, so in many ways it is a summary of the diary entries found therein. Important overall global warming effects were noted, including:

Increasing surface air temperature

The graphic below shows the annual mean temperature anomaly (compared to 30 year 1981-2010 mean) of the Arctic and the globe as a whole for the last 121 years. Notice that the warming in the Arctic is amplified since 2000 by about a factor of 2. This Arctic amplification has long been predicted by climate models.

Mean annual SAT anomalies (in °C) for weather stations located on Arctic lands, 60-90° N (red line), and globally (blue line) for the 1900-2021 period (n=122 years). Each temperature time series is shown with respect to their 1981-2010 mean. Sources: CRUTEM5 SAT data are obtained from the Climate Research Unit (University of East Anglia) and Met Office. From arctic.noaa.gov/....

Verification by the World Meteorological Organization (WMO) of the highest temperature ever observed in the Arctic in Verhoyansk

Greening of the tundra

From the 2021 Arctic Report Card; maximum seasonal greenness trend over 2000-2021.

Data on the amount of active vegetation has been measured by satellite for the past 39 years. Arctic-wide greenness in 2021 was the 2^nd highest among those years.
The growing season has begun, on average, 2.3 ± 0.7 days earlier per decade, and has ended 1.3 ± 0.9 days later per decade. On Svalbard, in the Norwegian Sea, ground-based cameras and satellite data showed that the 2018 growing season started 10 days earlier than in 2017. This shows that year-to-year variability can be quite large.
Some regions are bucking the overall trend. One area (blue oval in graphic) has browned over a 2000-2021 period. This has been attributed to permafrost melt making the surface soils wet enough to inhibit tundra growth.

Decreasing Arctic sea ice

Monthly sea ice extent anomalies (solid lines) and linear trend lines (dashed lines) for March (black) and September (red) 1979 to 2021. The anomalies are relative to the 1981 to 2010 average for each month. Source: arctic.noaa.gov/...

The Arctic Ocean sea ice melt season was somewhat less extreme than some previous seasons, but ranked 12th lowest since 1979. The last 15 years have had the 15 lowest minimum sea ice extent.
The area sea ice trends from March (maximum) and September (minimum) 1979-2021 are shown in the 1^st graphic to the right. Both show statistically significant decreases over the 43-year period. For September, the year-to-year changes are more noisy than those for March, which can result in short-term trends that differ from the long-term decline.
The bottom graphic shows the change in sea ice age (a proxy for sea ice volume) from 1985 to 2021 [(a) and (b)], and the trend in the area of ice lasting multiple years during the period. We can also clearly see the decrease in minimum sea ice area over the 37 year period. Note also the previously large area of multiyear ice (light blue through red) is now less than half of the total ice area. In 1985, almost all of the sea ice was multiyear.

The line graph at the bottom shows the year-to-year trend of multiyear and 4-year and older Arctic sea ice, consistent with the Arctic Ocean maps.

Sea ice age coverage map for the week before minimum total extent (when age values are incremented to one year older) in (a) 1985, and (b) 2021; (c) extent of multiyear ice (black) and ice >4 years old (red) within the Arctic Ocean for the week of the minimum total extent.
Source: arctic.noaa.gov/…

Intensifying Arctic water cycle

According to the 2021 Arctic Report Card:

Arctic river discharge is a key indicator reflecting changes in the hydrologic cycle associated with widespread environmental change in the Arctic.

It impacts:

Arctic Ocean salinity, and thus the seawater density and sea ice formation
The geochemistry of the Arctic Ocean (11% of global surface water discharge into 1% of global ocean water)
The biological activity at the bottom of the Arctic food chain (algae)

Watersheds of the eight largest Arctic rivers that are featured in this analysis. Collectively, these rivers cover approximately 70% of the 16.8 million km² pan-Arctic watershed (indicated by the red boundary line). The red dots show the locations of the discharge monitoring stations.
Source: arctic.noaa.gov/...

The graphic above shows the eight largest river basins as measured by river discharge in the Arctic. These cover 70% of the total Arctic watershed. Six of these river basins are in Eurasia (Kolmya, Lena, Yenisey, Ob’, Pechora, and Severnaya Dvina), while the other two are in North America (Mackensie and Yukon).

trends in arctic river discharge

Long-term trends in annual discharge (km³ yr^-1) for (a) Eurasian and (b) North American Arctic rivers through 2020. Gaps in the North American rivers time series span from 1996 through 2001 due to missing Yukon data (1996 to 2001) and missing Mackenzie data (1997 and 1998). Dashed lines show the mean annual discharge throughout the 1981-2010 reference period for the Eurasian (1860 km³ yr^-1) and North American (491 km³ yr^-1) rivers.
Source: arctic.noaa.gov/...

On the right are the trends for the (a) Eurasian and (b) North American annual river discharges since about 1935 and 1976, respectively. Both are strongly statistically significant. For the Eurasian watersheds particularly, the speedup of the Arctic water cycle is apparent from the trend. Year-to-year variations in discharge are the result of spring water equivalent snow cover. Higher water equivalent leads to higher total discharge.

Annual cycle of arctic river discharge

In general, maximum discharges come earlier in the spring than in the past. This can, depending on timing with relation to the calendar month, lead to anomalously high monthly river discharges followed by anomalously low ones. In 2020, this phenomenon was observed for the Eurasian basins, with May discharge at well over 99% above normal, but June discharge at about 99% below normal. This was the result of high Eurasian snow cover melted away at a record pace during a record warm spring, coinciding with the month of May.

Glacial and permafrost melt

Melting glaciers and thawing permafrost impact human infrastructure, lives, and ecosystems in significant ways. Entire hillsides can give way and coastlines can melt into the sea, taking structures with them.

We can see the locations of hazard areas in the Arctic below. The grey to blue shades show general areas of permafrost, while the brown circles show the locations of specific permafrost hazards. Dark blue circles show the location of glacier hazards.

Examples of observed glacier and permafrost hazards in recent years. Locations of hazard events are presented along with current glacier/ice sheet and permafrost extent, roads and pipelines, populated places (graduated circles scaling with population), and shipping routes.
Permafrost, Brown et al. (1997); Cities and glaciers, Natural Earth data; Infrastructure, OpenStreetMap; Hazard data, LEO Network; Shipping, Berkman et al. (2020); Hydrant photo, G. Hagle; Tsunami photo, Joint Arctic Command 2021; Avalanche photo, R. Frauenfelder
Source: arctic.noaa.gov/...

We’ve seen pictures of roadways for example, where the permafrost has melted from below. Here’s an example of a road damaged by permafrost thawing by the National Park Service in Wrangell- St. Elias Preserve, AK.

Road damage by permafrost melt in Wrangell-St. Elias National Preserve, AK. Source: www.nps.gov/....

When permafrost melts below trees and shrubs, they randomly tilt in such a haphazard way that the area becomes known as a “drunken forest”. The example below was also taken at Wrangell- St. Elias Preserve, AK.

Example of permafrost thawing under a forest of conifers in Wrangell-St. Elias National Preserve, AK. Source: www.nps.gov/....

Other items include the emerging disruptions of ocean noise resulting from the loss of sea ice and increased commercial ship traffic, and the expansion of the effective range of the beaver into the Alaskan tundra (beaver pond numbers up by a factor of 2). The beaver ponds act as a disrupter of permafrost and are transforming lowland tundra ecosystems. Additionally, record amounts of foreign trash from ship traffic piled up along the Siberian and Alaskan shorelines of the Bering Strait.

Disruption of the Antarctic Ice Shelf

I was going to add some information about the possibility of the Antarctic ice shelf holding back the Thwaites Glacier disintegrating in the next three to five years, but I see that Pakalolo has done his usual thorough and informative job on that subject. You can see what I mean here.

Conclusions

Changes in the Arctic continue apace. Mostly a warmer and wetter climate trend will continue over the long term, with lots of variability from year to year and a continuation of ecosystem disruptions resulting from loss of sea ice, permafrost, and temperature/precipitation changes. Things beyond beavers may find their way into the Arctic as conditions become more favorable to them. Changes will often occur in unexpected and disturbing ways, as we have seen in recent years.

Climate Brief: Arctic switch to more rain than snow now expected 10-20 years earlier

billlaurelMD

Community (This content is not subject to review by Daily Kos staff prior to publication.)

Friday December 03, 2021 · 4:13 PM PST

2021/12/03 · 16:13

A melting Greenland glacier in cloudy, foggy conditions.

Introduction

An Historical First: Rain at Greenland Summit Station

Some of you may recall the report that on August 21, 2021, rain was observed at the highest point on the Greenland Ice Sheet, 3250 m (10663 ft) above sea level. Not only that, but temperatures were above freezing for eight consecutive hours for only the fourth time in the historical record going back to 1950, but the third time since 2012. This observation is clearly related to global warming, which is amplified in the polar regions. On that day, there was an estimated 7 billion tons of rainfall on the ice sheet, resulting in a loss of surface ice mass the next day that was seven times above the mid-August average, according to the National Snow and Ice Data Center.

What the Climate Models Had Been Telling Us, and What They Say Now

Until recently, it was thought that by around the turn of the century (2090-2100), the Arctic would switch from more snow than rain to the opposite in the summer and fall (Climate Model Intercomparison Project (CMIP) 5). More recent research (CMIP6) has been done using better climate models which are better able to simulate Arctic (and global) precipitation and offer insights into the ways rain and snow patterns may shift over the coming decades. They now suggest that this transition will now most likely occur between 2060-2070, about 20-30 years earlier, and:

… at a lower level of global warming, potentially under 1.5 °C, with profound climatic, ecosystem and socioeconomic impacts.

McCrystall, M.R., Stroeve, J., Serreze, M. et al. New climate models reveal faster and larger increases in Arctic precipitation than previously projected. Nat. Commun. 12, 6765 (2021). https://doi.org/10.1038/s41467-021-27031-y

Retrospectives of the 1979-2005 period using reruns of CMIP5 and CMIP6 models show a modest increase of 0.1mm/day, consistent with what’s been observed, so at least over the past 26 years the climate models are reasonably representing the climate at the time. Additionally, spatial patterns of high and low precipitation are consistent with observations. Incidentally, the ratio of snow to total precipitation dropped over that retrospective period by a statistically significant −6% across the observational record.

summary of model results

Changes in the ratio of rain and snow are seen in the graphics below, taken from the Nature Communications article previously referenced. The top graphic shows DJM (winter) and MAM (spring), while the bottom graphic shows JJA (summer) and SON (autumn).

Climate model simulations from historic period through 2100 for the worst case scenario (business as usual). On the left is the results for winter, on the right the results for spring. The Arctic includes all areas poleward of 70^oN.

In winter, Arctic area-averaged total precipitation increases by about 0.6 mm/day (2.83” for the season) in CMIP6, and by about 0.5 mm/day (2.43” for the season) in the older CMIP5. There is a significant difference in the rain versus snow partitioning of precipitation between the old and new climate simulations; in the old CMIP5, rain increases at the same rate as snow through 2100. In CMIP6, 0.3 mm/day more rain than snow occurs by 2100, while only 0.1 mm/day more water equivalent of snow occurs. Spring shows only half of the change in total precipitation for the simulations, but with more rain than snow in both simulations after is somewhat higher than in winter for both simulations. The proportional increase in rain is largest in the CMIP6 runs.

Climate model simulations from historic period through 2100 for the worst case scenario (business as usual). On the left is the results for summer, on the right the results for autumn. The Arctic includes all areas poleward of 70^oN.

For the summer season, Arctic total precipitation increases by about 0.3 mm/day in CMIP6 (0.25 mm/day in CMIP5) by 2100. We see that the proportion of precipitation that falls as rain continues to increase for the summer season (by 0.65 mm/day in CMIP6 and 0.5 mm/day in CMIP5). Snow water equivalent decreases significantly in both global warming climate runs, by 0.25 mm/day in CMIP5 and 0.3 mm/day in CMIP6. Finally, autumn total precipitation increases by about 0.8 mm/day (3.78” for the season) in CMIP6, and by about 0.6 mm/day (2.83” for the season) in the older CMIP5. The largest difference between CMIP6 and CMIP5 occurs in autumn for rainfall (1.05 mm/day and 0.8 mm/day) and for snow water equivalent (0.4 mm/day vs about 0.18 mm/day). This is likely because of less Arctic sea ice leading to warmer temperatures at least for the first part of autumn.

Implications of Earlier Shift to More Arctic Rain Than Snow

Impact of Increased Precipitation and Rain on Reindeer/Caribou

So, what are these “profound climatic, ecosystem and socioeconomic impacts? One is the increase in Arctic precipitation resulting from global warming and its amplification in the Arctic. One resulting ecosystem impact has already been occurring and is devastating: the depletion of caribou herds in Lapland and the Arctic Archipelago because of starvation. Why are they starving? Because global warming has thrown the caribou out of sync with their environment. Additionally, the vegetation that the caribou need in the winter has been more difficult to forage because of deeper than normal snow (increased precipitation generally), or rain freezing on the snow to make it virtually impenetrable (more cold season rain). According to the Yale School of the Environment:

Thirty-four of the 43 major herds that scientists have studied worldwide in the last decade are in decline, with caribou numbers plunging 57 percent from their historical peaks. Some populations have fallen precipitously: The Bathurst herd in Canada’s central Arctic has plummeted from a peak of 472,000 in 1986 to 32,000 today — a drop of 93 percent.

Finally, deep snow or ice make it more difficult for caribou to outrun their biggest predator, wolves.

Many changes resulting from warming are conspiring against the caribou, from increased insect populations (that torment them while they are trying to eat) to replacement of lichens with small shrubs and the introduction of new infectious diseases. These negative environmental changes are certainly affecting many other Arctic species, including human beings.

Impacts of More Rainfall on Snow Fields, Glaciers/Ice Sheets and Permafrost

Snow cover and snow depth are important modulators of climate. A shorter snow season results in more absorption of incoming solar radiation. This in turn causes earlier Arctic green-up (or green-up where previously there was none), generally warmer soils to a further depth, and further thawing of permafrost with increasing methane release and damage to infrastructure such as roads, buildings, and pipelines. Furthermore, more rain and less snow results in lower accumulations of snow mass to add annually to existing ice sheets, including Greenland. Rain falling on snow, even if it doesn’t result in bare surfaces, changes the characteristics of the snow, including reduction of its albedo, again increasing absorption of solar radiation.

All things considered, it seems likely there will be increases in the proportion of rain to snow over the rest of the 21st century. The timing and degree of that increase is the only thing in doubt, and that will depend on the mean global temperature and that of the Arctic.

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