”Oh oh, I’ve seen fire, and I’ve seen rain, I’ve seen sunny days I though would never end”
”I’ve looked at clouds from both sides now”
Well, you knew I was going to have to go there. So I just got it out of the way right off the weather vane. Thank you James Taylor, and thank you Joni Mitchell.
The atmosphere. It’s like the Department of Motor Vehicles; sometimes you hate living with it but you just can’t live without it.
In Part 1, Tectonic, I showed some of the ways in which the natural forces of volcanoes and the shifting of oceanic and land masses have, from not long after the formation of Earth right up to the present day, been both fundamental and essential to the evolution of life on Earth. In today’s diary we will see how our atmosphere has likewise been a forceful driver in determining which life forms have arisen, evolved, survived, and gone extinct. The focus will be on three facets of the atmosphere: wind, rain, and fire.
The Daily Bucket is a nature refuge. We amicably discuss animals, weather, climate, soil, plants, waters and note life’s patterns.
We invite you to note what you are seeing around you in your own part of the world, and to share your observations in the comments below.
Each note is a record that we can refer to in the future as we try to understand the phenological patterns that are quietly unwinding around us. To have the Daily Bucket in your Activity Stream, visit Backyard Science’s profile page and click on Follow.
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Before we go on, let’s get a sense of just what our atmosphere really is. That’s easy. It’s a blanket.
Canadian Space Agency
The atmosphere is the blanket of gases which surrounds Earth. It is held near the surface of the planet by Earth's gravitational attraction.
Without the atmosphere there could be no life on Earth. The atmosphere:
- contains the air we breathe;
- protects life from harmful radiation from the Sun;
- helps keep the planet's heat from the Sun from escaping back into space;
- is a major element of the water cycle;
- keeps the climate on Earth moderate compared to that of other planets.
The atmosphere is made up of a mixture of gases, mostly nitrogen, oxygen, argon and carbon dioxide. It reaches over 500km above the surface of the planet. There is no exact boundary between the atmosphere and outer space. Atmospheric gases become thinner the higher up you go. The atmosphere just keeps getting less and less dense, until it "blends" into outer space.
The wind brings in the seasons, carries seeds and pollen from place to place, knocks old, dying, and dead trees down so new ones can take over, and even helps non-flying animals, like some spiders, move about.
Wind is essential to natural processes.
Wind has the ability to help things move, that otherwise couldn’t, around their environment. Seeds are one of the most common things that are moved by the wind. In fact, the term anemochory refers to the dispersal of seeds by wind. This includes milkweed seeds that use a parachute mechanism, dandelion seeds that use a pappus, maple seeds that use a samara and cattail seeds that use fine, silky hairs to disperse seeds from the parent plant using the wind. And these are just a few examples of plants that use the wind to disperse seeds and, subsequently, plant populations.
Other plants use the wind to create seeds. Many trees, especially pine and oak trees, use the wind to disperse pollen with the hope that the pollen will travel to and fertilize a viable egg where, under the right conditions, a seed will develop. Insects may help the process, but if you have ever lived in an area dominated by pine and oak trees, you’ve seen the generous amounts of pollen released by the male structures. It’s a natural mechanism to ensure that the genetic material in the pollen will fertilize as many eggs as possible, thereby passing on the legacy of the tree.
In addition, wind blowing on a small seedling or newly emerged spring plant helps the plant create a stronger stem. Each time a plant is pushed by the wind, it releases a hormone called an auxin that stimulates the growth of supporting cells. Research has shown that this is actually beneficial to the plant, and that plants that begin growth in the absence of wind tend fall over or break more easily than those grown in the presence of some wind. Anyone who has ever started garden plants from seeds has probably experienced this. The best way to avoid wind damage to seedlings is to place them outside for short periods of time each day, to “harden off” the plants from the effects of the wind and direct sunlight.
Can you think of any other non-flying animals that have at least partially used the wind for transportation?
Rain is the elixir of life. Without rain, there would be no fresh water on earth. Without the atmosphere there would be no rain. It’s a “circle of life” kind of thing.
The Fundamentals of the Water Cycle:
Where does all the Earth's water come from? Primordial Earth was an incandescent globe made of magma, but all magmas contain water. Water set free by magma began to cool down the Earth's atmosphere, until it could stay on the surface as a liquid. Volcanic activity kept and still keeps introducing water in the atmosphere, thus increasing the surface- and groundwater volume of the Earth.
The water cycle has no starting point. But, we'll begin in the oceans, since that is where most of Earth's water exists. The sun, which drives the water cycle, heats water in the oceans. Some of it evaporates as vapor into the air. Ice and snow can sublimate directly into water vapor. Rising air currents take the vapor up into the atmosphere, along with water from evapotranspiration, which is water transpired from plants and evaporated from the soil. The vapor rises into the air where cooler temperatures cause it to condense into clouds.
Air currents move clouds around the globe, cloud particles collide, grow, and fall out of the sky as precipitation. Some precipitation falls as snow and can accumulate as ice caps and glaciers, which can store frozen water for thousands of years. Snowpacks in warmer climates often thaw and melt when spring arrives, and the melted water flows overland as snowmelt.
Most precipitation falls back into the oceans or onto land, where, due to gravity, the precipitation flows over the ground as surface runoff. A portion of runoff enters rivers in valleys in the landscape, with streamflow moving water towards the oceans. Runoff, and groundwater seepage, accumulate and are stored as freshwater in lakes. Not all runoff flows into rivers, though. Much of it soaks into the ground as infiltration. Some water infiltrates deep into the ground and replenishes aquifers (saturated subsurface rock), which store huge amounts of freshwater for long periods of time.
Some infiltration stays close to the land surface and can seep back into surface-water bodies (and the ocean) as groundwater discharge, and some groundwater finds openings in the land surface and emerges as freshwater springs. Over time, though, all of this water keeps moving, some to reenter the ocean, where the water cycle "ends" ... oops - I mean, where it "begins."
I do love rain, whether gentle and calming or furious and wild. Of all the elements of the atmosphere though, the one that excites me the most is lightning. Lightning can be downright terrifying, of course, and it’s mysterious, fleeting, and often destructive. Lightning brings fire down on earth, but even fire is essential to life processes on Earth.
Why are Fires Important?
Fires play an important role in the natural changes that occur in Earth's ecosystems. The diversity of plant and animal life in the world's forests, prairies, and wetlands is (partly) dependent on the effects of fire; in fact, some plants cannot reproduce without fire (fire breaks open the outside coating of some seeds and stimulates germination). What may at first look like total devastation soon becomes a panorama of new life. Fire initiates critical natural processes by breaking down organic matter into soil nutrients. Rain then moves these nutrients back into the soil providing a rejuvenated fertile seedbed for plants. With less competition and more sunlight, seedlings grow more quickly.
I’ve never been a firefighter and have never wanted to be one. This year California went through it’s worst-ever fire season.
NBC News: [bolding mine]
Oct. 4, 2020, 2:53 PM PDT
By Tim Stelloh
ALAMEDA, Calif. — California marked a grim milestone Sunday as the number of acres burned during a record wildfire year surpassed 4 million, officials said.
The California Department of Forestry and Fire Protection, or Cal Fire, didn't provide an exact amount of land that had been scorched this year, but it said in a daily statewide summary that more than 8,200 fires have burned "well over" 4 million acres.
Annual statistics from the department dating to 1987 show that 2020 has more than doubled the previous record.
As many as 20,000 firefighters, some coming from as far away as Israel, have responded to scores of major fires across the state this year. Thirty-one people have died.
The largest, most destructive blazes have occurred since mid-August, when thousands of lightning strikes sparked dozens of fires in Northern California, including the largest wildfire in state history, the nearly 1 million-acre August Complex fire, which is burning across six counties.
I hope we have learned something from this.
And I hope you have learned something from this diary. I know I have; I’ve learned at least one new word: anemochory. I can’t wait to use that in a conversation.
So, wind, rain, and fire (lightning). Here’s all three at once, outside my place, although the “fire” isn’t immediately apparent:
Now It's Your Turn
What have you noted happening in your area or travels? Anything been flowin’ or blowin’ in your world? As usual post your observations as well as their general location in the comments.
Thank you.
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"SPOTLIGHT ON GREEN NEWS & VIEWS" WILL BE POSTED EVERY SATURDAY AT NOON PACIFIC TIME AND EVERY WEDNESDAY AT 3:30 PACIFIC TIME ON THE DAILY KOS FRONT PAGE. BE SURE TO RECOMMEND AND COMMENT IN THE DIARY.
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