Excited to be able to share this comprehensive review on the many ways that climate change is increasing bushfire risk in southeast Australia, just published in @CommsEarth.

Thread
👇 describing what we found:

[paper is open

This was a huge collaborative effort across climate and fire science experts, including from @ClimateExtremes and @BushfireHub, who came together following the #BlackSummer disaster in Australia.

Our review focuses on forest fires in southeast Australia (NSW + ACT + Victoria).
The #BlackSummer fires were unprecedented:

*In their scale (23% of all southeast Australia forests were burnt)

*In their power (for every month of the spring and summer seasons), and

*In the number of fires that developed into extreme pyroconvective events
Climate in SE Australia in 2019 was also the hottest and driest on record.

Regional warming is part of human-caused global warming trend.

Dry conditions were part of a 3-year drought with consecutive winter rain failures. Long-term winter drying trend appears to be emerging.
Dry years in southeast Australia are usually also hot, (and wet years are usually cool), due to land-atmosphere feedbacks.

And years of large bushfires in southeast Australia have clustered in the hot-&-dry quadrant of historical climate conditions
Climate variability also contributed to the extreme climate in 2019.

The phases of climate variability that increase fire risk in southeast Australia are El Niño events, positive Indian Ocean Dipole events, and a negative Southern Annular Mode in the warm season.
Having two or more of the climate modes have been in their fire-promoting phase significantly increases the risk of large fires.

In 2019 the compound effects of +IOD and -SAM increased the extent and severity of fire risk in southeast Australia.
But climate variability is also being altered by climate change.

Fire-promoting phases of tropical climate variability have now become more frequent than any time in the last several hundred years.
In Australia, the forest fire danger index (FFDI) is used to describe fire risk.

High FFDI reflects conditions where fuels burn readily and dangerous fire weather make fire difficult to control.
There are criticisms of the FFDI, including that it was developed using data from low intensity fires and prior to human-caused climate warming.

Despite this, FFDI has continued to be a good indicator of historical fires, including the #BlackSummer fires.
A linear increase in FFDI has been associated with an exponential intensification of fire radiative power.

Radiative power and FFDI in southeast Australia were both the highest ever recorded in December of 2019.
Unprecedentedly high FFDI during the #BlackSummer was also matched by:
*the largest forest burn area ever recorded, and
*the greatest number of extreme pyroconvective events ever observed.
Forest fire danger in SE Australia has now emerged above the range of historical experience.

FFDI emergence is greatest in spring/summer.

Emergence also evident in Vapour Pressure Deficit – one of the prime factors linked to increasing fire risk in other parts of the world.
The observed signal of emergence suggests that predictions made more than a decade ago of a directly observable effect of climate change on fire danger in southeast Australia by 2020 have indeed eventuated.
Looking to the future, we then reviewed the various climate changes that are expected in southeast Australia.

Some of these changes are virtually certain, others still have moderate or only low scientific confidence.
We then mapped how these climate changes would alter the essential ingredients (fuel load, fuel dryness, fire weather, ignition) needed for large forest fires.

Climate change is expected to increase fire risk in many ways, esp. through drier fuels and more dangerous fire weather
Most of the response to the Black Summer fires has focused on how to be better prepared for future fires.

But climate change will continue to increase fire risk in southeast Australia, possibly at a very rapid rate.

https://t.co/jergTykcdf
A low greenhouse gas emission future would limit how much worse fire risk gets in the future, and give adaptation measures the best chance of success.

More from News

.@louiscasiano from @FoxNews reached out to ask if we are actually planning on contaminating the hotel rooms of Proud Boys with bedbugs. The short answer is no, we don't even know if that's possible. But here's our full response.


That post was clearly satire. We have no idea how one would actually go about the activity that was suggested.

What is not satire are the numerous death threats that were sent to us by Trump supporters in the lead up to the November election.

Here are a few tweets depicting detailed and credible death threats that you didn’t ask for comment on:
https://t.co/UiI12M0Aey.
https://t.co/PPe75XWImX
https://t.co/4Ia8659wK8
https://t.co/n5ov6R8Gyh


Each of those tweets includes the email address of the sender. We wish you luck in reaching out to them for comment.

Further, the hate crimes committed by the Proud Boys during their last visit to DC were not satire. A marauding band of drunk white nationalists stormed through our city, tearing down and burning religious symbols declaring respect for Black lives.
A quick thread on the new variant, pulling together information from news sources, twitter, genomic databases, and word from well-placed peers.


The new variant in the UK consists of several mutations in the spike protein, including ΔH69/ΔV70 deletions & other receptor binding domain mutations such as N501Y.

The variant is described here in this pre-print from @GuptaR_lab.

https://t.co/ui2U1r1ANA


The ΔH69/ΔV70 variant continues to increase quite rapidly as a proportion of overall positives (roughly doubling in the last 2 to three days), and is apparently now the dominant strain in test positives in some regions.

Extensive efforts have gone into enhanced surveillance for the ΔH69/ΔV70 deletion with and without RBD mutations, and it is good that we are aware of this.

There is a need for calm and rational thinking, and more evidence is needed.

But the early data is certainly concerning

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