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About Rasmus Benestad

I am a senior scientist working at the Norwegian Meteorological Institute with a background from physics. My scientific career started with a degree in Physics with Electronics at UMIST in Manchester (UK), cloud micro-physics at New Mexico Tech (USA), and ocean physics at Atmospheric Oceanic and Planetary Physics (AOPP) at Oxford University (UK). Since then, I have also got heavily involved in the field of statistics, thanks to exciting collaborations with several statisticians.

My primary focus at the Norwegian Meteorological Institute has been towards climate change adaptation, empirical-statistical downscaling and anthropogenic climate change, but I have also worked on problems relating to natural climate variations connected to changes in the sun. I have authored two text books on these topics: Solar Activity and Earth's climate (Praxis/Springer) and Empirical-Statistical Downscaling (World Scientific Publishers).

My experience from the climate science community includes several roles: a contributing author on two past IPCC assessment reports, a person of contact (POC) for World Climate Research Programme's (WCRP) CORDEX project, a coordinating lead author on Arctic Monitoring and Assessment Programme's (AMAP) report Adapting Actions in a Changing Arctic (AACA, 2017), a councilor for the European Meteorological society (EMS), a member of the EMS communication and media committee, and part of the advisory board for Oxford Research Encyclopedia on climate. I also chair the professional network within the Norwegian trade union for engineer and natural scientists Tekna Klima, dealing with a diverse range of climate solutions.

Area-based global hydro-climatological indicators

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The World Meteorological Organisation (WMO) Global Climate Observing System (GCOS) and Copernicus Climate Change Services (C3S) both provide sets of global climate statistics to summarise the state of Earth’s climate. They are indeed valuable indicators for the global or regional mean temperature, greenhouse gas concentrations, both ice volume and area, ocean heat, acidification, and the global sea level.

Still, I find it surprising that the set does not include any statistics on the global hydrological cycle, relevant to rainfall patterns and droughts. Two obvious global hydro-climatological indicators are the total mass of water falling on Earth’s surface each day P and the fraction of Earth’s surface area on which it falls Ap.  

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Evaluation of GCM simulations with a regional focus.

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Do the global climate models (GCMs) we use for describing future climate change really capture the change and variations in the region that we want to study? There are widely used tools for evaluating global climate models, such as the ESMValTool, but they don’t provide the answers that I seek.

I use GCMs to provide information about large-scale conditions, processes and phenomena in the atmosphere that I can use as predictors in downscaling future climate projections. I also want to know whether the ensemble of GCM simulations that I use provides representative statistics of the actual regional climate I’m interested in. 

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The summary for policymakers of the Intergovernmental Panel on Climate Change sixth assessment reports synthesis

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The summary for policymakers of the Intergovernmental Panel on Climate Change (IPCC) sixth synthesis report was released on March 20th (available online as a PDF). There is a recording of the IPCC Press Conference – Climate Change 2023: Synthesis Report for those who are interested in watching an awkward release of the report.

It strikes me that the IPCC perhaps assumes that everyone is climate literate and are up to speed on climate change. While many journalists clearly got the message, expressed through news reports though e.g. the Guardian and Washington Post, I doubt that relevant leaders were swayed. One problem may be that journalists do not carry as much weight as scientists. 

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The established ground and new ideas

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Science is naturally conservative and the scepticism to new ideas ensures high scientific quality. We have more confidence when different scholars arrive at the same conclusion independently of each other. But scientific research also brings about discoveries and innovations, and it typically takes time for such new understanding to receive acknowledgement and acceptance. In the meanwhile, it’s uncertain whether they really represent progress or if they are misconceived ideas. Sometimes we can shed more light on new ideas through scientific discussions.

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Serious mistakes found in recent paper by Connolly et al.

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Guest post by Mark Richardson who is a Research Scientist in the Aerosol and Clouds Group at NASA’s Jet Propulsion Laboratory, California Institute of Technology. All opinions expressed are his own and do not in any way represent those of NASA, JPL or Caltech.

Should scientists choose to believe provably false things? Even though that would mean more inclusive debates with a wider range of opinions, our recent paper Richardson & Benestad (2022) argues no: “instead of repeating errors, they should be acknowledged and corrected so that the debate can focus on areas of legitimate scientific uncertainty”. We were responding to Connolly et al., who suggested that maybe the Sun caused “most” of the warming in “recent decades” based on a simple maths mistake. 

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References

  1. M.T. Richardson, and R.E. Benestad, "Erroneous use of Statistics behind Claims of a Major Solar Role in Recent Warming", Research in Astronomy and Astrophysics, vol. 22, pp. 125008, 2022. http://dx.doi.org/10.1088/1674-4527/ac981c

The #ConcordOslo2022 workshop

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In recent years, the idea of climate change adaptation has received more and more attention and has become even more urgent with the unfolding of a number of extreme weather-related calamities. I wrote a piece on climate change adaptation last year here on RealClimate, and many of the issues that I pointed to then are still relevant. 

The dire consequences of flooding, droughts and heatwaves that we have witnessed the last couple of years suggest that our society is not yet adapted even to the current climate. One interesting question is whether the climate science community is ready to provide robust and reliable information to support climate change adaptation when the world finally realises the urgency to do so. In other words, we need to know how to use the best available information the right way. 

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New misguided interpretations of the greenhouse effect from William Kininmonth

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I have a feeling that we are seeing the start of a new wave of climate change denial and misrepresentation of science. At the same time, CEOs of gas and oil companies express optimism for further exploitation of fossil energy in the wake of Russia’s invasion of Ukraine, at least here in Norway.

Another clue is William Kininmonth’s ‘rethink’ on the greenhouse effect for The Global Warming Policy Foundation. He made some rather strange claims, such as that the Intergovernmental Panel on Climate  Change (IPCC) allegedly should have forgotten that the earth is a sphere because “most absorption of solar radiation takes place over the tropics, while there is excess emission of longwave radiation to space over higher latitudes”. 

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Future rainfall over Sahel and Sahara

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Ethiopia is praying for rain according to a recent report from the Guardian, and ReliefWeb suggests that a lack of rain may be linked to malnutrition in Tchad, as well as reduced crops in Niger. 

The African rainfall deficit appears to be widespread: the Cairo Review reports severe droughts that have been experienced across the Sahel, the Horn of Africa, and Southern Africa in 2011 and 2020. But the picture is also more complicated, as heavy rains have unleashed massive flooding across South Sudan according to the Red Cross.

A similar ambiguity can also be seen in the future prospects for this region. The recent Intergovernmental Panel on Climate Change (IPCC) report (Assessment Report 6, often referred to as ‘AR6’) presents maps showing projected changes in the precipitation, e.g. in Figure SPM.5 and the IPCC Atlas. 

The most recent precipitation projections reveal a remarkable dark green blob covering parts of Sahel and Sahara in addition to the Arabian peninsula, suggesting that this dry region may be blessed with more rainfall in the future (e.g. Figure 1). 

Figure 1. A map from Figure SPM.5 from IPCC AR6 slides, showing percentage change in annual mean precipitation from a historical baseline (1850-1900). These results represent the Coupled Model Intercomparison Project phase 6 (also known as ‘CMIP6’) Global Climate Models (GCMs). 

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A science-based move to climate change adaptation

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All countries in the world urgently need to adapt to climate change but are not yet in a good position to do so. It’s urgent because we are not even adapted to the present climate. This fact is underscored by recent weather-related calamities, such as flooding in Central Europe and heatwaves over North America. It’s also urgent because the oceans act like a flywheel, making sure that cuts in emission of greenhouse gases will have a lagged effect on global warming.

Climate change adaptation was addressed in the Paris Agreement from 2015, the Climate Adaptation Summit in January 2021, and will be one of four key priorities during the upcoming COP26. Proper climate adaptation of course needs meteorological and climatological data for mapping weather-related risks to prepare us for future extreme weather. However, I would argue that the climate research community has not had a visible presence during any of these meetings. Instead the summits have been dominated by politicians and NGOs.

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Deciphering the ‘SPM AR6 WG1’ code

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I followed with great interest the launch of the sixth assessment report Working Group 1 (The Physical Science Basis) from the Intergovernmental Panel on Climate Change (IPCC) on August 9th. 

The main report is quite impressive (see earlier posts here, here, here, and here) but the press conference didn’t come across as being focused and well-prepared. In my opinion the press conference on 9 August 2021 didn’t do justice to the vast effort that went into it.

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