The upcoming Arctic outbreak across Central U.S. is going to be the "real deal". Temperatures will likely rival anything seen in 30 years (or even longer!) across portions of the Central Plains. In a warming climate, that's saying quite a lot. #COwx#NEwx#WYwx#KSwx (1/6)
Temperatures will fall, in incredibly dramatic fashion ( of the course of just a few hours) by 40 or more degrees in some areas as a powerful Arctic front pushes through. Temperatures will plummet well below zero (-20 to -30F) across a broad region, w/even lower windchills. (2/6)
This level of cold will be potentially dangerous even in places accustomed to pretty low temperatures in winter, since even those spots haven't seen temperatures this low in 30 or more years. This will be especially true across portions of Wyoming and Colorado. #WYwx#COwx (3/6)
One personal reflection as a climate scientist currently living in Boulder: it's plausible that these are the coldest temperatures I'll experience in this part of the world for the rest of my life, given the strong and sustained winter warming trend due to #ClimateChange. (4/6)
Winters across essentially the entire U.S. have been getting warmer in recent decades, with decreases in both the duration and magnitude of extreme cold in most places. #ColdSnap#ClimateChange#ArcticBlast (5/6)
Finally, a brief note about amplified Arctic warming & its influence on mid-latitude cold snaps: right now, evidence suggests that although warming Arctic may well have regional/seasonal effects on jet stream, it's probably not causing more extreme winter cold in N. America.(6/6)
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The mass firing of both new hires and recently promoted senior staff within #NOAA, including mission-critical and life-saving roles at the National Weather Service (#NWS), is profoundly alarming.
1/11
It appears that staff fired today include meteorologists, data scientists responsible for maintaining weather predictive models, and technicians responsible for maintaining the nation’s weather instrumentation network (among many others).
2/11
The U.S. NWS is a truly world-class meteorological predictive service, perhaps singularly so. Its cost of operation is only ~$3-4/yr per taxpayer—equivalent to a single cup of coffee—and yields a truly remarkable return on investment (at least 10 to 1, and perhaps 100 to 1).
3/11
A period of very warm mid-winter conditions appear likely for much of California and portions of the interior West in late Feb. A strong ridge will form during this period, with large-scale subsidence & warm air advection allowing for a genuine winter "heat wave" next week. #CAwx
Temps in 80s will be widespread in SoCal, & even 90s are possible. T-shirt and shorts weather will also extend into NorCal and beyond (well into 70s), as well as desert SW (where late spring-like temps in 90s are likely). Late Feb records may be broken in some places. #CAwx #AZwx
Looking ahead to the end of winter and spring, the California/U.S. West precipitation dipole (i.e., unusually wet in the north and unusually dry in the south) appears likely to continue. The dryness may expand to include more of CA/West Coast later in spring, too. #CAwx #CAwater
Out today in @GlobalChangeBio is our (brief!) rapid-response piece on the broader context surrounding the January 2025 Southern California wildfires & relevance of wet-to-dry hydroclimate whiplash to fire both locally and globally on a warming Earth. [1/8] onlinelibrary.wiley.com/doi/full/10.11…
@GlobalChangeBio Coastal Southern California experienced an exceptional wet-to-dry "hydroclimate whiplash event" between May/June 2024 (following a second anomalously wet winter) and Dec/Jan 2024/5 (characterized by the driest start to season on record in many parts of the region). [2/8]
@GlobalChangeBio This whiplash event caused a pronounced vegetation accumulation-then-desiccation cycle, adding more fuel for (potential) fires to come then drying it out to record levels for time of year--setting stage for destructive fires when strong winds arrived.[3/8] onlinelibrary.wiley.com/doi/full/10.11…
After becoming increasingly enmeshed in the wildfire world, you start to notice things about the way we've systematically altered our relationship with the natural environment in a way that has increased the risk of destructive fires. And then you stop being able to unsee them.
I've always lived in the American West, in different parts of California and on the Colorado Front Range. I've traveled throughout the West extensively; even as a child, fire was always there in the distance--a companion on family roadtrips, a backdrop to summer afternoons.
One of my earliest memories (fuzzy though it is; I was very young) was ash falling from the sky while out at a San Francisco park. The date? October 20, 1991--the day the devastating Oakland Hills fire tore through around 3,000 structures and killed 25 in the Berkeley Hills.
Our paper on "Hydroclimate volatility on a Warming Earth" is out in Nature Reviews Earth & Environment. We assess existing scientific literature & conduct new analysis--concluding that "#HydroclimateWhiplash" is increasing due to #ClimateChange. [Thread] nature.com/articles/s4301…
"Hydroclimate volatility" refers to rapid transitions between unusually wet & dry conditions relative to local baseline. For quantitative analysis, we define a new "hydroclimate whiplash" metric using Standardized Precipitation & Evaporation Index (SPEI). nature.com/articles/s4301…
One key aspect of the framework for understanding such volatility is that it encompasses both "supply" & "demand" side of water balance--that is, not only precipitation (or lack thereof), but also evaporation (or evaporative demand). Precipitation doesn't tell the whole story!
Is there a link between #ClimateChange & increasing risk/severity of #wildfire in California--including the still-unfolding disaster? Yes. Is climate change the only factor at play? No, of course not. So what's really going on? [Thread] #CAfire #CAwx #LAfires iopscience.iop.org/article/10.108…
There is rarely, if ever, a singular cause of complex disasters--so don't be fooled by disingenuous "straw man" binaries! For wildfire, encroachment into high risk areas, historical land management, & climate all matter (to contextually varying degrees). theguardian.com/environment/20…
What is the primary link between #ClimateChange and wildfire, both in CA specifically and more broadly globally? Vegetation moisture, and therefore its flammability (which includes propensity to ignition, combustion intensity, rates of spread, and etc.). nature.com/articles/s4155…