"Uncertainty is not our friend here," said Penn State climate scientist Michael Mann. "We are seeing increases in extreme weather events that go well beyond what has been predicted or projected in the past. We're learning that there are factors we were not previously aware of that may be magnifying the impacts of human-caused climate change." Among those are "subtle mechanisms involving the behavior of the jet stream that may be involved in explaining the dramatic increase we've seen in floods, droughts, heat waves and wildfires," he said.
"Increasingly, the science suggests that many of the impacts are occurring earlier and with greater amplitude than was predicted," Mann said, after considering new research since the milestone of the IPCC's Fifth Assessment, which served as the scientific basis for the Paris Agreement.
"We have literally, in the space of a year, doubled our assessment of the potential sea level rise we could see by the end of this century. That is simply remarkable. And it is sobering," he said.
In general, there should be more monitoring of global warming impacts, but all those programs are threatened under the current administration, Mann said. "Continued funding to support research is critical," he said, "and here, again, we encounter a very unfavorable political environment where fossil fuel-beholden politicians that run the White House and Congress are doing everything they can to defund and suppress research on climate change science and impact assessments."