12 February 2018

Do we have the capability to reverse global warming within a meaningful timeframe?

"Do we have the capability to reverse global warming within a meaningful timeframe?" was the topic for discussion at the Sustainable Living Festival's Great Debate on 9 February 2018. The contributions to the discussion by David Spratt and Ian Dunlop are reproduced here. Ian and David are also the authors of the recent reports What Lies Beneath: the scientific understatement of climate risks and Disaster Alley: Climate change, conflict and risk.

DAVID SPRATT

The present 1°C of climate warming is already dangerous because critical tippings points have already been crossed. In 2014 glaciologist Eric Rignot said ice retreat in parts of West Antarctica was already “unstoppable”, with the “likely collapse of the rest of the ice sheet, and a 3-5 metre sea level rise”. That is, unstoppable unless temperatures decline below 1°C to the 1970s level.
In Paris in 2015, the rhetoric was of 1.5°C and 2°C, even as the voluntary, unenforceable agreements put warming on a path to 3°C, and perhaps 4°C.

But 1.5°C is far from safe. A safe climate would be well less than the current warming, unless you think it is OK to destroy the Arctic ecosystem, tip West West Antarctic glaciers into a self-accelerating melt, and lose the world’s coral reefs, just for starters.

01 February 2018

Quantifying our Faustian bargain with fossil fuels

Our Faustian bargain: the byproduct of burning dirty
fossil fuels are short-lived atmospheric aerosols
which provide temporary cooling
by David Spratt

The climate system will heat well past 1.5 degrees Celsius (°C) and perhaps up to 2°C without any further fossil fuel emissions. That’s the conclusion to be drawn from new research which should also help demystify the rhetoric from the 2015 Paris climate talks of keeping warming to below 1.5°C .

It’s not that 1.5°C isn’t dangerous: in fact, at just 1–1.1°C of warming to date, climate change is already dangerous. A safe climate would be well below the present level of warming, unless you think it is OK to destroy the Arctic ecosystem, tip West West Antarctic glaciers into a self-accelerating melt, and lose the world’s coral reefs, just for starters.

The new research quantifies the effect of losing the very temporary planetary cooling provided by atmospheric aerosols.

22 January 2018

New study on climate sensitivity not what poor media headlines, deniers are saying

Courtesy Skeptical Science
One swallow doesn't make a spring, and nor does one scientific paper change a whole body of evidence. But you could be mistaken for thinking so after the poor media coverage last week of a new piece of climate research.

A study published last week in Nature ("Emergent constraint on equilibrium climate sensitivity from global temperature variability") claims to tighten the Intergovernmental Panel on Climate Change (IPCC), range for (short-term) Estimated Climate Sensitivity (ECS), the amount of warming to be expected from a doubling of carbon dioxide  (CO2) in the atmosphere.

19 January 2018

Displacing coal with wood for power generation will worsen climate change, say researchers

The Drax facility in North Yorkshire has transitioned some of its coal power generation capacity to wood pellets with the support of UK government subsidies
New research has challenged the view that wood bioenergy is carbon neutral, and shows that wood pellets burned in European and UK power plants actually emit more carbon dioxide (CO2) per kilowatt hour than that generated by coal.

This is because wood is both less efficient at the point of combustion and has larger processing and supply chain emissions than coal. Their research shows that using wood instead of coal in power generation increases the amount of CO2 in the atmosphere, worsening climate change until—and only if—the harvested forests regrow.

15 January 2018

What we learned about the climate system in 2017 that should send shivers down the spines of policy makers

by David Spratt

Much of what happened in 2017 was predictable: news of climate extremes became, how can I put it … almost the norm. There was record-breaking heat on several continents, California’s biggest wildfire (extraordinarily in the middle of winter), an ex-tropical cyclone hitting Ireland (yes, Ireland) in October, and the unprecedented Hurricanes Harvey, Irma and Maria that swept through the Atlantic in August. The US government agency, the NOAA, reported that there were 16 catastrophic billion-dollar weather/climate events in the USA during 2017.

And 2017 “marks the first time some of the (scientific) papers concluded that an event could not have occurred — like, at all — in a world where global warming did not exist. The studies suggested that the record-breaking global temperatures in 2016, an extreme heat wave in Asia and a patch of unusually warm water in the Alaskan Gulf were only possible because of human-caused climate change”, Reuters reported.