Wildfire smoke will slow down warming. New science with Dr. Edward Blanchard-Wrigglesworth in Seattle. It’s big. Plus drought advancing, becoming more extreme due to global warming. Lead Author Solomon Gebrechorkos from Oxford explains. Potsdam research scientist Stefan Rahmstorf on AMOC collapse. New maps of extreme cold in Europe’s future. Plus more on warming acceleration.

Listen to or download this Radio Ecoshock show in CD Quality (57 MB) or Lo-Fi (14 MB)

 

Another war. Troops in the streets of Los Angeles. China factory shutdowns. Global stocks and bonds shudder. Uncertainty reigns. Welcome to Radio Ecoshock – the world’s emergency room. But remember boys and girls, no matter what we do, ocean currents roar on, clouds cluster or fade, and more solar energy builds up on this planet. Major scientists can barely be heard as they warn: “Global Warming has Accelerated Significantly”.

We are warming four times faster than in the 1900’s. Young people today could live through a crash of civilization. One important new factor: drought is increasing in recent decades, and getting more extreme, even in places where annual rainfall has not changed. I pass on results from new science and an interview with Lead Author Solomon Gebrechorkos from Oxford.

But a new factor, not included in the models, is hiding some of the warming already caused. So many wildfires are burning in Canada and Siberia that their smoke is cooling Earth significantly. New science finds if these rates of wildfire smoke continue into the future, there could be 12% less warming than expected. Most of the cooling happens in the far north, with a 38% drop from expected. Wildfires may temporarily cool the Earth and slow down Arctic sea ice loss. If humans decide to fight those fires, and succeed, then the full warming of our emissions will be revealed. It is another “Faustian Bargain” as James Hansen calls it.

 

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HOW WILL WILDFIRE SMOKE AFFECT CLIMATE?

EDWARD BLANCHARD-WRIGGLESWORTH

In recent years, wildfire smoke floods skies in the Northern Hemisphere. It is happening right now. Could fire smoke reduce future warming? Does it affect Arctic sea ice? Big climate models don’t include this growing force in the atmosphere. A new paper covers it all.

The Lead Author has the skills to bring it together. Edward Blanchard-Wrigglesworth was part of a NASA science team monitoring polar ice. He studied Boreal fires, Polar predictability, and interaction of atmosphere and the sea. Edward is Research Associate Professor in the Department of Atmospheric Sciences at the University of Washington in Seattle.

Edward Blanchard-Wrigglesworth

Listen to or download this 25 minute interview with Edward Blanchard-Wrigglesworth in CD Quality or Lo-Fi

 

When sulfates in ship emissions were reduced by new regulations, veteran NASA scientist James Hansen said the clean-up revealed more warming, maybe a jump in temperature in the last couple of years. Edward confirms the cooling potential from wildfires is similar to the sulfates found in ship emissions.

We start with a concrete case. In June 2023 skies over New York City turned orange during the day. According to a peer-reviewed publication from Rutgers, smoke from mass wildfires in Canada cooled New York by 3 degrees Celsius, over five Fahrenheit. That a good example of the cooling in this new study study.

Even the paper title contains a lot. The title is “Increasing boreal fires reduce future global warming and sea ice loss”. The Abstract says:

“…we find that increasing boreal emissions reduce global warming by 12% and Arctic warming by 38%, reducing the loss of sea ice. Tropical precipitation shifts southward as a result of the hemispheric difference in boreal aerosol forcing and subsequent temperature response.”

ALEX SAYS…

Still, we know this cooling by Boreal wildfire aerosols is short-lived (being rained out in weeks) – except for any impact of ice formation, which might delay actual heat. Otherwise, the carbon released by Boreal wildfires lasts 100,000 years at least, is not rained out, and definitely heats the planet even more.

Also: if aerosols from wildfires create more condensation nuclei for clouds and eventually for rain, the changed rain patterns would slowly change the landscape below, not just in plant life, but geologically, as some lakes disappear and others appear, or extreme rainfall erosion, etc. While aerosols might decline, landscape changes would remain as a record of the time of fire…

This team finds boreal biomass burning emissions are “reducing sea ice loss”. Yet sea ice is at a record low. Could Arctic sea ice have disappeared altogether in Summer (a “Blue Ocean event”) – if not for wildfire aerosols?

Assuming wildfires and their smoke increase in the future, and their impact will largely be in the half-year summer burning season, will this increase or decrease the difference between seasons? Will wildfires change the seasons?

BOREAL WILDFIRES CHANGE LARGE PRECIPITATION PATTERNS

The new study finds:

“In addition to changes in global and regional warming patterns, we also find impacts on other key aspects of the climate system as a result of increased boreal fires. Precipitation decreases in the northern high latitudes, while tropical precipitation shifts southward.”

FOLLOW-UP TO EDWARD BLANCHARD-WRIGGLESWORTH INTERVIEW

I had trouble with a couple of numbers in the new paper. For example, it says “increasing boreal emissions reduce global warming by 12% and Arctic warming by 38%”. Cutting global warming by 12% would be astonishing! Do the authors mean a reduction of 12% compared to previous projections by global climate models, or 12% of the expected 2 to 3 degree C warming on our current path?

Edward sent me a follow-up explanation by email. He writes:

“The 12% indicates the reduction in the rate of warming, so the total global-mean warming is still 88% of the default simulation. The default simulation (without boreal fire increase) global-mean temperature warms at 0.37°C per decade, whereas with the boreal fires the global-mean temperature warms at 0.33°C per decade.

And the 12% reduction refers indeed to the global-mean temperature, but it doesn’t mean that the warming decreases by 12% at each single location on the planet. In fact, we see that the warming is reduced mostly in the northern latitudes (where in the Arctic the reduction is 38%), whereas in the tropics and southern hemisphere, there’s hardly any difference in the warming. So, the 12% global-mean number essentially is a result of a stronger than 12% slowdown in northern regions, and a weaker, or no change in slowdown, in other (southern) regions. “

That comes from University of Washington researcher Edward Blanchard-Wrigglesworth.

Although surprising, this sounds possible. Just for explanation, let’s say models show by 2100 the world warms another 2 degrees C hotter than today, given our emissions. But come 2100, Earth is only 1.76 degrees C hotter – because of cooling by on-going wildfire smoke. The smoke cools the Arctic a lot (38%). That may be enough to show up in the average for the whole world, making it 12% lower than expected.

That still leaves us with a world 3.26 C hotter than pre-industrial! Disaster. But it would have been 3.5 C hotter without the fire smoke.

As another scientist put it: “Wildfire smoke aerosols cause strong atmospheric warming and large surface cooling”.

Key in all this, a wide group of scientists warn human-induced or natural aerosols (particles in the air) can cool the Earth significantly. They may also stimulate formation of more clouds, another cooling agent.

So powerful are tiny particles of pollution that former Goddard Director James Hansen says reduced ship pollution revealed a bump in warming as high as .5 degrees C. Not all scientists agree, but everyone agrees clouds can fundamentally change the balance of solar power staying on the planet. Just a thinning of clouds or fewer forming in the tropics lead to significant changes, especially around the tropics.

As Blanchard-Wrigglesworth points out, this leads to a big question: what if humans try to control fires in the North? We may do it to reduce the very dangerous health impacts of smoke pouring south into big cities from Seattle to New York, or in Northern China. Or we may calculate releasing that much carbon from the trunks of trees is too dangerous for the atmosphere. Burned over north-lands may also expose carbon rich peat to more heat, speeding up thaw of permafrost and decomposition of peat. On a large scale, that could release significant warming. We may need new spending or new technology to control pollution and the burst of carbon from wildfires.

But if we reduce wildfires from their current massive annual burns – that will reveal even more warming from our greenhouse gases. Removing that much smoke is like turning off the air-conditioner. Now you get the real temperature, just as when ship emissions were reduced after 2020.

Keep in mind: the impact of wildfire smoke is NOT included in big climate models and projections by the Intergovernmental Panel on Climate Change (IPCC). The 2006 IPCC Guidelines explains why wildfire emissions were not counted in preparing national emissions inventories.

“Wildfires and other disturbances on unmanaged land cannot, in general, be associated to an anthropogenic or natural cause, and hence are not included in the 2006 Guidelines, unless the disturbance is followed by a land-use change.“

The new study authors say expected increase in Boreal wildfires is expected to be linear, not exponential, in part because of “the negative fuel-availability feedback.” – namely there will be less to burn in the future.

SEE ALSO

Impacts of wildfire smoke aerosols on radiation, clouds, precipitation, climate, and air quality

Rahele Barjeste Vaezi et al. in Atmospheric Environment; X April 2025

GLOBAL WARMING IS ACCELERATING

To wrap it up:

1. we have already heated the world more than we know because some of the warming is hidden by shade from human pollution and wildfire smoke.

2. this is the Faustian bargain James Hansen wrote about. If we clean up the pollution, or control northern wildfires, we feel the real heat of what we’ve done to the atmosphere and oceans.

3. real warming is almost always at the high end of any error bars in climate models, the higher numbers in estimates

4. it is possible, as Hansen and a few others insist, that climate sensitivity is greater than previously thought. That means we warm faster with less carbon dioxide and methane added to the atmosphere. If true, this is as serious as a heart attack.

The now-retired from NASA James Hansen is not very retired. He continues to publish papers with other scientists, but does so through his Columbia University blog, without peer-review. Hansen prefers to work on his own, often outside the general global scientific community.

In recent work, Hansen claimed global warming was accelerating, and insinuated mainstream science missed it. Experts like Michael Mann from Penn U. were critical, saying recent warming was still within the error bars or upper limits predicted by formal groups, like the Intergovernmental Panel on Climate Change.

 

Factcheck: Why the recent ‘acceleration’ in global warming is what scientists expect

 

There is new support for heat acceleration, predicted or not. Stefan Rahmstorf has a pre-print paper titled “Global Warming has Accelerated Significantly”. That was posted March 3, 2025 and now there is revised version June 8.

Picking Up Speed

 

Rahmstorf is not part of the usual James Hansen team of authors. Stefan is a German oceanographer and climatologist, a long-time Professor of Physics of the Oceans at Potsdam University. He is also Head of Research Department at PIK, the Potsdam Institute for Climate Impact Research. Rahmstorf is well-known in the community for his authoritative posts at the blog realclimate.org.

Here is the Abstract:

“Recent record-hot years have caused a discussion whether global warming has accelerated, but previous analysis found that acceleration has not yet reached a 95% confidence level given the natural temperature
variability.

Here we account for the influence of three main natural variability factors: El Niño, volcanism, and solar variation. The resulting adjusted data show that after 2015, global temperature rose significantly faster than in any previous 10-year period since 1945.”

Basically, there are 5 major computing centers storing global observations of temperature, both land and sea surface. They are operated by NASA, NOAA, the Hadley Centre-Climate Research Unit in the UK, Berkeley, and the European Centre for Medium-Range Weather Forecasts (ECMWF). Each has slightly different figures for end of 2024 warming over pre-industrial. The average of all is 1.46 degrees C of warming – barely under the 1.5 degree Paris Climate Accord supposed safety line not to cross.

The European center says we already crossed 1.5 C in 2024. Every other model predicts this will happen in 2026. Across all observation sets, we appear to be warming by .43 degrees C per decade. Just for comparison, global average surface temperature has risen at an average rate of 0.17°C per decade since 1901. Earth is warming four times faster than in the previous century!

Dutch amateur scientist Leon Simons created a handy chart which assumes no further acceleration of warming. Just heating up at our current rate (.43 per decade) – the world crosses the dangerous 2 degree C threshold in 2037. It’s 2.5C hotter in 2048, crazy hot, very soon, within the lives of most of you. Three degrees C comes in 2060 and an astonishing 3.5 degrees C in 2072 – still within the lives of young people today.

Somewhere between 2054 and 2065 Earth might be 3 degrees C hotter, that is 5.4 degree F on a GLOBAL AVERAGE. That includes warming in the hard-to-heat ocean. A lot of experts believe civilization could not survive the climate emerging from that level of heat. Maybe a billion people would have to leave the overheated tropics. Crops would fail, with all that means for social stability. Add in storms super-charged by hotter oceans and we might need a new Cat 6 or more to describe them.  The world will not end, but human civilization would be under exceptional strain within 30 years.  Some say collapse is inevitable at 3 degrees warmer than pre-industrial.  Next week I will be interviewing plant experts trying to adapt key staple crops to grow in a hotter world.

Canadian systems scientist Paul Beckwith has a good YouTube video out June 10, also titled “Global Warming Has Accelerated Significantly”. You can see Leon Simons’ chart there. Look for Paul H Beckwith on YouTube.

 

 

These heating projections do not include possible tipping points that could speed things up even faster! It does not include any further acceleration. This one lifetime jump in heat is based only on current observations taken from weather buoys, land stations and satellites, which reflects greenhouse gases we already pushed into the atmosphere.

Nothing in the future is guaranteed. A chain of volcanoes, erupting for years, could temporarily cool Earth. But when they stop, and their ash is washed out by rain, then true warming returns with a vengeance. The same is true if humans inject sulfates into the atmosphere as geoengineering. If that program stops, for war, pestilence or any other reason, real warming returns quickly. Or we could be hit with an asteroid which changes everything.

All those are long-shots. Realists know: we are in a climate emergency. No matter what wars and hatred run through our minds, no matter what we believe or do not believe, climate change is happening. We can respond and try to save ourselves. Or live a last great party of frivolous pyres of burning carbon. It’s your choice.

MORE DROUGHT AS HUMANS OVERHEAT THE PLANET

Let’s look at new science showing more severe droughts will develop as we heat the planet. According to the latest from EU science center Copernicus, it has been an exceptionally dry spring in parts of north-western Europe. More drought are popping up all over the world, from Africa through Asia. In some years severe drought hit the U.S. Southeast and main crop growing regions in the United States and Russia. Drinking water can also run out. AI data farms, gas electricity plants and nuclear reactors all have to shut down without enough cooling water.

Outside those human affairs, animals suffer and die. Plant communities may die off, to be replaced with more tolerant invader species. The insect world and essential fungi change. You can’t show drought in news video. It’s not big on social media. But increasing drought can change the world.

We also have reports and science on “flash droughts”. A severe drying of the soil can occur within days when the air is hot and dry. Plants wilt or die. In the right conditions, a flash drought can develop within days of rainfall. I covered flash droughts with Brian Ancell from Texas Tech University, in my show published April 20, 2022.

Drought, Superstorms, War And Vision

 

REVEALING NEW STUDY OF DROUGHT & WARMING

SOLOMON GEBRECHORKOS 

Are droughts increasing as the world warms? Is climate change a driver? Everything from crops to drinking water and plant life depends on the answer. Getting the right answers is not as easy as you think.

A new paper, June 4th in Nature, has the big picture. The title is: “Warming accelerates global drought severity”. The Lead Author is Solomon Gebrechorkos, Research Associate at Oxford’s School of Geography and the Environment. Solomon edits three climate science journals. He has dozens of papers on hydrology, the study of how water moves around on this planet.

 

I spoke with Solomon, but technical problems plagued the recording. I’m going to quickly summarize our conversation and the new paper. The Abstract is pretty clear:

“Drought is one of the most common and complex natural hazards affecting the environment, economies and populations globally. However, there are significant uncertainties in global drought trends, and a limited understanding of the extent to which a key driver, atmospheric evaporative demand (AED), impacts the recent evolution of the magnitude, frequency, duration and areal extent of droughts.

Here, by developing an ensemble of high-resolution global drought datasets for 1901–2022, we find an increasing trend in drought severity worldwide. Our findings suggest that AED has increased drought severity by an average of 40% globally. Not only are typically dry regions becoming drier but also wet areas are experiencing drying trends. During the past 5 years (2018–2022), the areas in drought have expanded by 74% on average compared with 1981–2017, with AED contributing to 58% of this increase.

The year 2022 was record-breaking, with 30% of the global land area affected by moderate and extreme droughts, 42% of which was attributed to increased AED. Our findings indicate that AED has an increasingly important role in driving severe droughts and that this tendency will likely continue under future warming scenarios.”

That was the Abstract from the June 4 paper in Nature “Warming accelerates global drought severity”. You can read more in this article in The Conversation by Solomon, published June 4, 2025.

I’m now wondering – if more plants die out due to drought, that means less carbon capture by plants. As warming disturbs the water cycle, drought-stricken plants could absorb less carbon dioxide, increasing warming – a feed back loop?

WHO GETS DRYER AND WHO WETTER

In May I interviewed Stanford’s David Lobell about crop loss. Water Vapor Deficit was cited as a major driver of crop loss in the United States.  In the new Nature paper, looking at short droughts, six months or less, they found a serious drying trend in Europe, Africa, western North America and South America. Some regions get wetter in Southeast Asia, the Caribbean coast of South America, parts of Africa and eastern North America.

FOCUS ON EUROPE

I’ve assembled quotes from the paper relevant to drought in Europe, home to three quarters of a billion people.

“In Europe, 82% of land experienced drought, with 50% under moderate to severe drought. In 2022, annual precipitation across Europe dropped by up to 35% below the 1981–2022 average, and AED increased by up to 40%… “

“The year 2022 specifically was a record-breaking year for drought severity and extent in Europe and East Africa. In Europe, the severity of the 2022 drought event can be largely attributed to anthropogenic warming, as the anomalies observed in stream flow and soil moisture cannot be explained by the precipitation deficit alone, but mostly by enhanced AED, which increased water losses by evaporation”

“Moreover, the ecological drought severity recorded in Europe’s natural forests cannot be fully explained without considering the influence of high temperatures and AED on plant physiology. In the absence of formal attribution studies in other regions of the world that experienced drought in 2022, the attribution in Europe and the increase in severity globally driven by enhanced AED as shown in this study suggests that it is reasonable to conclude that anthropogenic global warming likely contributed to exacerbate global drought severity in 2022.”

“... the 2022 European drought, which contributed to enhanced tree mortality, increased forest fires and long-term soil moisture decline.”

OVERALL

For years, some scientists suggested we should talk about “global wetting” instead of “global warming”. According to physics, the warmer atmosphere should suck up a lot more moisture. Whether the air reaches capacity for water vapor varies greatly in different times, seasons, and continents. That is why Solomon and other scientists can still warn about more extreme drought for some parts of the world.

Watching repeated triple-digit heat waves, we might think extreme heat is killing crops. But the authors found a more serious threat. It is “vapor pressure deficit”. It often happens during high heat the air can hold much more water than it does. The dry atmosphere tries to suck moisture from plants and the soil. That, rather than heat, might be the true cause of crop damage.

I look at this like a gardener. Suppose there is a good season with enough rain, and then a three-week severe drought hits. Then it rains again. But if I don’t have irrigation or enough water in my hose, the garden dies in that short burst of drought. A lot plants don’t come back. We lose food. Multiply that times all the rain-dependent crops around the world – and you see the problem. Drought can be a game changer. Repeated droughts drive people out, leading to mass migration – even if the official annual rainfall has not changed.

In our conversation, Solomon told me the area affected by drought has expanded significantly, particularly during the past 5 years. About a quarter of land between 50 degrees South and 50 North experienced drought in the last 5 years. That is 74% higher than during during the period 1981–2017. Those are mind-crushing changes. You know about heatwaves. Get ready for “thirstwaves”.  You will hear more news reports in coming years of drought and failed crops. The so-called Vapor Pressure Deficit” will also fuel more extreme wildfires, sometimes in places you don’t “normally” expect them.

MORE WRINKLES IN DROUGHT

New science suggest another developing problem: “Recent Decline in Global Ocean Evaporation Due To Wind Stilling” led by Ning Ma. published: 19 February 2025 AND…

Science led by Matthew England found wind stilling over the North Atlantic led to record high sea surface temperatures but that led to enhanced evaporation there, possibly adding to severe downpours and floods in Europe during 2023. So there are positive and negative drivers of ocean evaporation as the world warms. Can we really predict which will be dominant?

EUROPE’S COLD SHIFT – A NEW LOOK

At least a dozen times I’ve interviewed scientists on this program about the weakening ocean current that carries tropical heat to Ireland, the UK, Northern Europe and Scandinavia. You can call it the Gulf Stream or the Atlantic Meridional Overturning Circulation or AMOC. Measurements of flow show that warm current is getting weaker as the world warms.

Exhaustive study of previous ages show this current can completely break down and almost stop flowing. The AMOC current appears to have a so-called “tipping point”, where the process of shutdown begins and cannot be reversed. Humans can’t change this giant ocean current, except by heating up the atmosphere.

What would it be like?  Physicist René van Westen has published a new paper with a vision of Europe after the Gulf Stream collapse.

Rene told Carbon Brief:

Ocean current ‘collapse’ could trigger ‘profound cooling’ in northern Europe – even with global warming

 

“If the AMOC collapses, we need to prepare for substantially cooler winters. Winter extremes will be very substantial for some regions. Temperatures could go down to -50C in Scandinavia. At -40C and lower in Scandinavia – everything breaks down over there.”

Along with the new Geophysical Research Letter by van Westen and Michiel Baatsen, there is an interactive map. You can tour the weather in Oslo or Dublin in the new cold regime – after the collapse, whenever that may be. The paper published June 11th is titled “European Temperature Extremes Under Different AMOC Scenarios in the Community Earth System Model”.

Quoting again from Carbon Brief June 11, 2025:

“The study suggests that, in an intermediate emissions scenario, greenhouse gas-driven warming would not be able to outweigh the cooling impact of an AMOC collapse.

In this modelled world, one-in-10 winters in London could see cold extremes approaching -20C.

Winter extremes in Oslo in Norway, meanwhile, could plummet to around -48C.

The cold temperatures are projected to be driven by the loss of heat transfer from the tropics via ocean currents, as well as the spread of sea ice to northern Europe in the winter months.

The research does not look at when AMOC might tip – instead, it focuses on scenarios in the far future when this has already happened, so as to explore what impact it would have.”

This Radio Ecoshock program ends with a short clip from BBC, recorded May 1, 2025 at the European Geosciences Union conference in Vienna. Correspondent Roland Pease talks with Professor Stefan Rahmstorf about AMOC collapse cooling Europe.

There you have it. More oddities in a changed world. At some point, Europe could have some bone-chilling cold winters even while the rest of the world is hot, hot, hot.

Remember, even during times of humans against humans, nature always wins.

I’m Alex Smith. Thank you for listening, and caring about this world.