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A potential rule of thumb for hourly rainfall?

Future global warming will be accompanied by more intense rainfall and flash floods due to increased evaporation, as a consequence of higher surface temperatures which also lead to a higher turn-around rate for the global hydrological cycle. In other words, we will see changing rainfall patterns. And if the global area of rainfall also shrinks, then a higher regional concentration of the rainfall is bound to lead to more intense downpours (the global rainfall indicator is discussed here). 

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Regional information for society (RifS) and unresolved issues

It’s encouraging to note the growing interest for regional climate information for society and climate adaptation, such as recent advances in the World Climate Research Programme (WCRP), the climate adaptation summit CAS2021, and the new Digital Europe. These efforts are likely to boost the Global Framework for Climate Services (GFCS) needed as a guide to decision-makers on matters influenced by weather and climate. 

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Don’t climate bet against the house

Decades ago (it seems) when perhaps it was still possible to have good faith disagreements about the attribution of current climate trends, James Annan wrote a post here summarizing the thinking and practice of Climate Betting. That led to spate of wagers on continued global warming (a summary of his bets through 2005 and attempts to set up others is here).

There were earlier bets, the most well known perhaps was the one for $100 between Hugh Ellsaesser and Jim Hansen in 1989 on whether there would be a new temperature record within three years. There was (1990), and Ellsaesser paid up in January 1991 (Kerr, 1991). But these more recent bets were more extensive.

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  1. R.A. KERR, "Global Temperature Hits Record Again", Science, vol. 251, pp. 274-274, 1991.

Climate Adaptation Summit 2021

Filed under: — rasmus @ 31 January 2021

The first ever Climate Adaptation Summit (#adaptationsummit) that I have heard about took place last week, on January 25-26. I think such a summit was a step in the right direction. It was adapted to the Covid-19 situation and therefore an online virtual summit streamed on YouTube

I watched a few of the streamed sessions, and it struck me that climate change adaptation seems to be a fairly new concept to many leaders. It were sometimes mix-ups with mitigation during the high-level talks. Mitigation and adaptation are both important and sometimes they overlap, so mix-ups are understandable. 

One important point addressed during the summit was of course financing climate change adaptation, which is promising. Financing is clearly needed for climate change adaptation. To ensure progress and avoid lofty visions without results on the ground, there may also be a need for tangible results and to show examples and demonstrations. One specific type discussed at the summit was “Early warning systems” which play an important role.

But it was not crystal clear what was meant by the concept “early warning systems”. My interpretation is that it involves something on par with weather forecasts which would imply that they are more about weather than climate. This is of course important too. Probably the first priority in many places. 

But early warning systems, the way I understand them, don’t provide information about climate risks on longer timescales. Weather and climate – short and long timescales – are of course connected but nevertheless different (“climate” can be viewed as weather statistics). Other examples of climate adaptation can be found in a recent Eos article on food security in Africa. I think it is important to mention maladaptation and avoid long-term problems connected to short-term fixes. Resilience is a keyword. 

As with many other summits, I felt that the scientists’ voice was largely missing. There seems to be a gap between high-level politics and science. I think we need a better dialogue between the leaders and climate scientists partly to help distinguish between different and difficult concepts. But the main reason is that we need to know what we must adapt to. We need to know the situation: the state of the climate and how it is changing. This knowledge is not readily downloadable from the Internet.

There are key questions that should involve scientists: What is needed for proper climate change adaptation? And what are the challenges in terms of meeting our objectives? What do we know about future risks? In addition, biodiversity, nature conservation, cultural, social and economic aspects are important. 

Data is crucial, but is often unavailable because of lack of sharing and lack of openness. Often due to lacking finance. Information about the regional climate change must be distilled from large volumes of data, and we need to ask what information is useful and how it can be used in the best possible way.

The required analysis is often carried out in climate services and often includes downscaling. It involves tools, methods and understanding that are still evolving with regards to these topics. This fact wasn’t explained clearly during the summit in the sessions I watched. I think it would be useful with a presentation of the state of climate science relevant for climate change adaptation at a high level in the summit. Perhaps science should get an equal amount of attention as the NGOs and the businesses. 

Much of the latest research relevant to the climate adaptation summit is coordinated within the World Climate Research Programme (WRCP) which also is setting a new focus on regional information for society (“RifS”). Furthermore, there is considerable scientific experience on adaptation from the Arctic with the fastest climate change on Earth, such as the Adaptive Actions in a Changing Arctic (AACA) report for the Arctic Council. 

Climate adaptation involves many communities and disciplines (e.g. weather forecasting, climate services, regional climate modelling, “distillation“, disaster risk reduction) which I think aren’t well coordinated at the moment. One message from the summit was “Let’s work together” which I think implies a better coordination of the different disciplines and communities.

Flyer tipping

Filed under: — gavin @ 12 January 2021

You would be forgiven for not paying attention to the usual suspects of climate denial right now, but they are trying to keep busy anyway.

Last week (January 8), Roy Spencer [Update Jan 13: now deleted] posted a series of Climate Change “flyers” on his personal blog that purported to be organised by David Legates (NOAA, detailed to Office of Science and Technology Policy (OSTP), nominally on leave from (and soon to return to) U. Delaware). Each was a rather garishly colored rehash of standard climate denial talking points, but featuring the OSTP official logo, and claiming to be copyrighted by OSTP (a legal impossibility). Note that if this was an official US Govt. work, they could not copyright them, but if it wasn’t, they could not legally use the OSTP logo to indicate that it was.

Dubious use of an official government logo…

The reaction to this definitive refutation of mainstream science (ha!) was… silence. Spencer’s post was reblogged at WUWT but again, nothing happened [Update Jan 13: Also now deleted]. . Many of the authors of the pieces themselves – many of whom are active on social media – didn’t bother to tweet or post about them. Odd.

The whole thing seems to be Legates trying to get a pet project out into the world before the new administration comes in, but without bothering with all that messy peer-review, official permission, proper channels or, you know, actual science. Almost certainly this is also a violation of the Data Quality Act, something Patrick Michaels (one of the flyer authors) was quite exercised about in his effort. Consistency is also apparently optional.

Anyway, a couple of days ago (Jan 10), they were also posted on Willie Soon’s new website where they were noticed on twitter, and today there have been some media eyebrows raised.

Is there a there there?

The flyers themselves are remarkably thin on valid argumentation. Will Happer’s discussion of Radiative Transfer is mostly textbook stuff except for the last paragraph where he simply asserts that a radiative forcing of 3 W/m2 can’t possibly matter. That’s kind of the key issue, which he totally elides.

Christopher Essex purports to discuss climate models, without ever showing anything from a climate model. He seems to be arguing against some Aristotelian concept of climate models that never has to be bothered with actually looking at the real world (for instance). Weird, and totally pointless.

Spencer makes the remarkable assertion that climate has changed for natural reasons in the past (I’m shocked, shocked!), and ignores how attribution actually works (I’m not at all shocked).

The Connollys and Willie Soon’s flyer purports to talk about sun-climate connections, but they spend most of their effort talking about Milankovitch forcing before pivoting to imagining a universe where the temperatures have not in fact been steadily climbing but where they could conceivably have a higher correlation to out-of-date and unsupported reconstructions of solar activity. In so doing, they even have the chutzpah to cite a paper of mine. Meh.

Etc. If there is a demand in the comments, I could expand on the others, but for now, I think you get the idea.

Why should anyone care?

Great question! I don’t think anyone should. But this whole effort is emblematic of how far the climate question has moved. With a new US administration poised to act on climate across a whole series of fronts, this feeble throwback (were they released on a Thursday?), serves to underline how out-of-touch these old school deniers and their talking points really are. This is perhaps the last weak ‘hurrah’ of a bankrupt cause.

Good riddance to bad rubbish.

Update (4pm, Jan 12): that was quick:

2020 vision

A meeting of smoke and storms (NASA Earth Observatory)

No-one needs another litany of all the terrible things that happened this year, but there are three areas relevant to climate science that are worth thinking about:

  • What actually happened in climate/weather (and how they can be teased apart). There is a good summary on the BBC radio Discover program covering wildfires, heat waves, Arctic sea ice, the hurricane season, etc. featuring Mike Mann, Nerlie Abram, Sarah Perkins-Kilpatrick, Steve Vavrus and others. In particular, there were also some new analyses of hurricanes (their rapid intensification, slowing, greater precipitation levels etc.), as well as the expanding season for tropical storms that may have climate change components. Yale Climate Connections also has a good summary.
  • The accumulation of CMIP6 results. We discussed some aspects of these results extensively – notably the increased spread in Equilibrium Climate Sensitivity, but there is a lot more work to be done on analyzing the still-growing database that will dominate the discussion of climate projections for the next few years. Of particular note will be the need for more sophisticated analyses of these model simulations that take into account observational constraints on ECS and a wider range of future scenarios (beyond just the SSP marker scenarios that were used in CMIP). These issues will be key for the upcoming IPCC 6th Assessment Report and the next National Climate Assessment.
  • The intersection of climate and Covid-19.
    • The direct connections are clear – massive changes in emissions of aerosols, short-lived polluting gases (like NOx) and CO2 – mainly from reductions in transportation. Initial results demonstrated a clear connection between cleaner air and the pandemic-related restrictions and behavioural changes, but so far the impacts on temperature or other climate variables appear to be too small to detect (Freidlingstein et al, 2020). The impact on global CO2 emissions (LeQuere et al, 2020) has been large (about 10% globally) – but not enough to stop CO2 concentrations from continuing to rise (that would need a reduction of more like 70-80%). Since the impact from CO2 is cumulative this won’t make a big difference in future temperatures unless it is sustained through post-pandemic changes.
    • The metaphorical connections are also clear. The instant rise of corona virus-denialism, the propagation of fringe viewpoints from once notable scientists, petitions to undermine mainstream epidemiology, politicized science communications, and the difficulty in matching policy to science (even for politicians who want to just ‘follow the science’), all seem instantly recognizable from a climate change perspective. The notion that climate change was a uniquely wicked problem (because of it’s long term and global nature) has evaporated as quickly as John Ioannidis’ credibility.

I need to take time to note that there has been human toll of Covid-19 on climate science, ranging from the famous (John Houghton) to the families of people you never hear about in the press but whose work underpins the data collection, analysis and understanding we all rely on. This was/is a singular tragedy.

With the La Niña now peaking in the tropical Pacific, we can expect a slightly cooler year in 2021 and perhaps a different character of weather events, though the long-term trends will persist. My hope is that the cracks in the system that 2020 has revealed (across a swathe of issues) can serve as an motivation to improve resilience, equity and planning, across the board. That might well be the most important climate impact of all.

A happier new year to you all.


  1. P.M. Forster, H.I. Forster, M.J. Evans, M.J. Gidden, C.D. Jones, C.A. Keller, R.D. Lamboll, C.L. Quéré, J. Rogelj, D. Rosen, C. Schleussner, T.B. Richardson, C.J. Smith, and S.T. Turnock, "Current and future global climate impacts resulting from COVID-19", Nature Climate Change, vol. 10, pp. 913-919, 2020.
  2. C. Le Quéré, R.B. Jackson, M.W. Jones, A.J.P. Smith, S. Abernethy, R.M. Andrew, A.J. De-Gol, D.R. Willis, Y. Shan, J.G. Canadell, P. Friedlingstein, F. Creutzig, and G.P. Peters, "Temporary reduction in daily global CO2 emissions during the COVID-19 forced confinement", Nature Climate Change, vol. 10, pp. 647-653, 2020.

Denial and Alarmism in the Near-Term Extinction and Collapse Debate

Guest article by Alastair McIntosh,  honorary professor in the College of Social Sciences at the University of Glasgow in Scotland. This is an excerpt from his new book, Riders on the Storm: The Climate Crisis and the Survival of Being

cover art for Riders on the StormMostly, we only know what we think we know about climate science because of the climate science. I have had many run-ins with denialists, contrarians or climate change dismissives as they are variously called. Over the past two years especially, concern has also moved to the other end of the spectrum, to alarmism. Both ends, while the latter has been more thinly tapered, can represent forms of denial. In this abridged adaptation I will start with denialism, but round on the more recent friendly fire on science that has emerged in alarmism.
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BAU wow wow

How should we discuss scenarios of future emissions? What is the range of scenarios we should explore? These are constant issues in climate modeling and policy discussions, and need to be reassessed every few years as knowledge improves.

I discussed some of this in a post on worst case scenarios a few months ago, but the issue has gained more prominence with a commentary by Zeke Hausfather and Glen Peters in Nature this week (which itself partially derives from ongoing twitter arguments which I won’t link to because there are only so many rabbit holes that you want to fall into).

My brief response to this is here though:

Mike Mann has a short discussion on this as well. But there are many different perspectives around – ranging from the merely posturing to the credible and constructive. The bigger questions are certainly worth discussing, but if the upshot of the current focus is that we just stop using the term ‘business-as-usual’ (as was suggested in the last IPCC report), then that is fine with me, but just not very substantive.


  1. Z. Hausfather, and G.P. Peters, "Emissions – the ‘business as usual’ story is misleading", Nature, vol. 577, pp. 618-620, 2020.

Sensitive But Unclassified

The US federal government goes to quite a lot of effort to (mostly successfully) keep sensitive but unclassified (SBU) information (like personal data) out of the hands of people who would abuse it. But when it comes to the latest climate models, quite a few are SBU as well.

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Just the facts?

In the wake of the appalling mass shootings last weekend, Neil DeGrasse Tyson (the pre-eminent scientist/communicator in the US) tweeted some facts that were, let’s just say, not well received (and for which he kind of apologised). At least one of the facts he tweeted about was incorrect (deaths by medical errors are far smaller). However, even if it had been correct, the overall response would have been the same, because the reaction was not driven by the specifics of what was said, but rather by the implied message of the context in which it was said. This is a key feature (or bug) of communications in a politicized environment, and one that continues to trip up people who are experienced enough to know better.

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