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About Raymond S. Bradley

Raymond Bradley is a Distinguished Professor in the Department of Geosciences at the University of Massachusetts, Amherst. His research focuses on climate variations over recent centuries and millennia. He has carried out extensive fieldwork in the Arctic and North Atlantic region (Canadian High Arctic, Greenland, Svalbard, the Faroe Islands and northern Norway).

Bradley did his undergraduate work at Southampton University (U.K.) and his post-graduate studies (M.A., Ph.D.) at the Institute of Arctic and Alpine Research, University of Colorado, Boulder. He also earned a D.Sc. from Southampton University, for his contributions in paleoclimatology.

Bradley has received honorary degrees (D.Sc honoris causa) from Lancaster University (U.K.), Queen’s University (Canada) and the University of Bern (Switzerland). He was awarded the Oeschger Medal of the European Geosciences Union and he received the Zuckerberg Leadership Chair from the University of Massachusetts Foundation.

He is a Fellow of the Royal Society of Canada, the American Geophysical Union, the American Association for the Advancement of Science, the Arctic Institute of North America, the Finnish Academy of Science and Letters, and the European Academy of Science.

Bradley has written or edited thirteen books on climatic change, and authored/co-authored more than 200 peer-reviewed articles on the topic.

A report from the European Meteorological Society’s annual meeting 2018

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If you want to make a difference as a scientist, you need to make sure that people understand the importance of your work. Conferences give you one opportunity to explain what you’ve found out.

I sometimes wonder if the value of attending conferences is sufficiently appreciated. You can save time getting an overview over your field of research and catch up on the latest developments, which would take many weeks just from reading papers (and it gets harder these days to find the time reading papers).

Another benefit is being able to meet colleagues and discuss the latest findings and your results. In addition to sharing your thoughts, you represent your institution and enhance its visibility. Organisations pay a lot of money for increased visibility. 

This week, I have listened to many good and interesting talks at the European Meteorological Society’s (EMS) annual meeting in Budapest (#emsannual2018), a meeting place for weather and climate experts across Europe and the rest of the world.

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Climate indicators

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The climate system is complex, and a complete description of its state would require huge amounts of data. However, it is possible to keep track of its conditions through summary statistics.

There are some nice resources which give an overview of a number for climate indicators. Some examples include NASA and The Climate Reality Project.

The most common indicator is the atmospheric background CO2 concentration, the global mean temperature, the global mean sea level, and the area with snow or Arctic sea ice. Other indicators include rainfall statistics, drought indices, or other hydrological aspects. The EPA provides some examples.   

One challenge has been that the state of the hydrological cycle is not as easily summarised by one single index in the same way as the global mean temperature or the global mean sea level height. However, Giorgi et al. (2011) suggested a measure of hydro-climatic intensity (HY-INT) which is an integrated metric that captures the precipitation intensity as well as dry spell length.  

There are also global datasets of indices representing the more extreme aspects of climate called CLIMDEX, providing a list of 27 core climate extremes indices (so-called the ‘ETCCDI’ indices, referring to the ‘CCl/CLIVAR/JCOMM Expert Team on Climate Change Detection and Indices’).

In addition, there is a website hosted by the NOAA that presents various U.S. Climate Extremes Index (CEI) in an interactive way.

So there are quite a few indicators for various aspects of the climate. One question we should ask, however, is whether they capture all the important and relevant aspects of the climate. I think that they don’t, and that there are still some gaps.

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References

  1. F. Giorgi, E. Im, E. Coppola, N.S. Diffenbaugh, X.J. Gao, L. Mariotti, and Y. Shi, "Higher Hydroclimatic Intensity with Global Warming", Journal of Climate, vol. 24, pp. 5309-5324, 2011. http://dx.doi.org/10.1175/2011JCLI3979.1

The claim of reduced uncertainty for equilibrium climate sensitivity is premature

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A recent story in the Guardian claims that new calculations reduce the uncertainty associated with a global warming:

A revised calculation of how greenhouse gases drive up the planet’s temperature reduces the range of possible end-of-century outcomes by more than half, …

It was based on a study recently published in Nature (Cox et al. 2018), however, I think its conclusions are premature.

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References

  1. P.M. Cox, C. Huntingford, and M.S. Williamson, "Emergent constraint on equilibrium climate sensitivity from global temperature variability", Nature, vol. 553, pp. 319-322, 2018. http://dx.doi.org/10.1038/nature25450

A brief review of rainfall statistics

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There have been a number of studies which show that we can expect more extreme rainfall with a global warming (e.g. Donat et al., 2016). Hence, there is a need to increase our resilience to more rainfall in the future.

We can say something about how the rainfall statistics will be affected by a global warming, even when the weather itself is unpredictable beyond a few days.

Statistics is remarkably predictable for a large number of events where each of them is completely random (welcome to thermodynamics and quantum physics).

The normal distribution has often been used to describe the statistical character of daily temperature, but it is completely unsuitable for 24-hr precipitation. Instead, the gamma distribution has been a popular choice for describing rainfall.

I wonder, however, if there is an even better way to quantify rainfall statistics.

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References

  1. M.G. Donat, A.L. Lowry, L.V. Alexander, P.A. O’Gorman, and N. Maher, "More extreme precipitation in the world’s dry and wet regions", Nature Climate Change, vol. 6, pp. 508-513, 2016. http://dx.doi.org/10.1038/nclimate2941

Impressions from the European Meteorological Society’s annual meeting in Dublin 

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The 2017 annual assembly of the European Meteorological Society (EMS) had a new set-up with a plenary keynote each morning. I though some of these keynotes were very interesting. There was a talk by Florence Rabier from the European Centre for Medium-range Weather Forecasts (ECMWF), who presented the story of ensemble forecasting. Keith Seitter, the executive director of the American Meteorological Society (AMS), talked about the engagement with the society on the Wednesday.

The Helix at DCU was the main venue of #EMS2017

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Why extremes are expected to change with a global warming

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Joanna Walters links extreme weather events with climate change in a recent article in the Guardian, however, some  reservations have been expressed about such links in past discussions.

For example, we discussed the connection between single storms and global warming in the post Hurricanes and Global Warming – Is there a connection?, the World Meteorological Organization (WMO) has issued a statement, and Mike has recently explained the connection in the Guardian.

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Snow Water Ice and Water and Adaptive Actions for a Changing Arctic

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The Arctic is changing fast, and the Arctic Council recently commissioned the Arctic Monitoring and Assessment Programme (AMAP) to write two new reports on the state of the Arctic cryosphere (snow, water, and ice) and how the people and the ecosystems in the Arctic can live with these changes.

The two reports have now just been published and are called Snow Water Ice and Permafrost in the Arctic Update (SWIPA-update) and Adaptive Actions for a Changing Arctic (AACA).

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