Climate science from climate scientists...
Gavin provided a thoughtful commentary about the role of scientists as advocates in his RealClimate piece a few weeks ago.
I have weighed in with my own views on the matter in my op-ed today in this Sunday’s New York Times. And, as with Gavin, my own views have been greatly influenced and shaped by our sadly departed friend and colleague, Stephen Schneider. Those who were familiar with Steve will recognize his spirit and legacy in my commentary. A few excerpts are provided below:
Back in 2007 I wrote a post looking at the closures of the Thames Barrier since construction finished in 1983. Since then there has been another 7 years of data* and given that there was a spate of closures last week due to both river and tidal flooding, it seems a good time to revisit the topic.
by Michael E. Mann and Gavin Schmidt
This time last year we gave an overview of what different methods of assessing climate sensitivity were giving in the most recent analyses. We discussed the three general methods that can be used:
The first is to focus on a time in the past when the climate was different and in quasi-equilibrium, and estimate the relationship between the relevant forcings and temperature response (paleo-constraints). The second is to find a metric in the present day climate that we think is coupled to the sensitivity and for which we have some empirical data (climatological constraints). Finally, there are constraints based on changes in forcing and response over the recent past (transient constraints).
All three constraints need to be reconciled to get a robust idea what the sensitivity really is.
A new paper using the second ‘climatological’ approach by Steve Sherwood and colleagues was just published in Nature and like Fasullo and Trenberth (2012) (discussed here) suggests that models with an equilibrium climate sensitivity (ECS) of less than 3ºC do much worse at fitting the observations than other models.
[Read more…] about A Bit More Sensitive…
We have often discussed issues related to science communication on this site, and the comment threads frequently return to the issue of advocacy, the role of scientists and the notion of responsibility. Some videos from the recent AGU meeting are starting to be uploaded to the AGU Youtube channel and, oddly, the first video of a talk is my Stephen Schneider lecture on what climate scientists should advocate for (though actually, it mostly about how science communicators should think about advocacy in general since the principles are applicable regardless of the subject area):
Since 1998 the global temperature has risen more slowly than before. Given the many explanations for colder temperatures discussed in the media and scientific literature (La Niña, heat uptake of the oceans, arctic data gap, etc.) one could jokingly ask why no new ice age is here yet. This fails to recognize, however, that the various ingredients are small and not simply additive. Here is a small overview and attempt to explain how the different pieces of the puzzle fit together.
Figure 1 The global near-surface temperatures (annual values at the top, decadal means at the bottom) in the three standard data sets HadCRUT4 (black), NOAA (orange) and NASA GISS (light blue). Graph: IPCC 2013. [Read more…] about The global temperature jigsaw
So, it’s that time of year again.
Fall AGU is the largest Earth Science conference on the planet, and is where you will get previews of new science results, get a sense of what other experts think about current topics, and indulge in the more social side of being a scientist. The full scientific program is available for searching here.
In recent years, there has been an increasing amount of virtual content – including live streaming of key sessions and high profile lectures, and continuous twitter commentary (follow the hashtag #AGU13), that give people not attending to get a sense of what’s going on. Gavin and Mike are attending and will try and give some highlights as the week goes along, here and via twitter (follow @ClimateOfGavin and @MichaelEMann).
Some obvious highlights (that will be live-streamed) are the Frontiers of Geophysics lecture from the Jim Hansen (Tuesday, 12:30pm PST), Senator Olympia Snowe (Monday, 12:30pm), Judith Lean (Tues 10:20am), the Charney Lecture from Lenny Smith (Tues 11:20am), James Elsner on tornado connections to climate change (Tues 2:40pm), David Grinspoon (the Sagan lecture, Thurs 9am), and Bill Ruddiman (Thursday 2:40pm). Some full sessions will also be livestreamed – for instance, The future of IPCC session (Tues 10:20am-12:30pm), and the Climate Literacy sessions (Tues 4:00pm-6:00pm, Wed 8am-12:30pm).
For attendees, there are a number of events close to our hearts: A bloggers forum for discussion on science blogging (Mon 5pm), the Open Mic night hosted by Richard Alley (Mon 7:30pm at Jillian’s Restaurant), and the AGU 5k run on Wednesday morning (6:30am).
Also AGU and the Climate Science Legal Defense Fund have organised a facility for individual consultations with a lawyer (by appointment via lawyer@climatesciencedefensefund.org) for people either who have found themselves involved in legal proceedings associated with their science or people who are just interested in what they might need to be prepared for. There is a brown bag lunch session on Friday (12:30pm PST) for a more informal discussion of relevant issues.
There are obviously many individual presentations that will be of interest, but too many to list here. Feel free to add suggestions in the comments and look out for updates all next week.
I was disappointed by the recent summary for policymakers (SPM) of the intergovernmental panel on climate change (IPCC) assessment report 5, now that I finally got around to read it. Not so much because of the science, but because the way it presented the science.
The report was written by top scientists, so what went wrong?
[Read more…] about A failure in communicating the impact of new findings
Lots of interesting methane papers this week. In Nature Geoscience, Shakhova et al (2013) have published a substantial new study of the methane cycle on the Siberian continental margin of the Arctic Ocean. This paper will get a lot of attention, because it follows by a few months a paper from last summer, Whiteman et al (2013), which claimed a strong (and expensive) potential impact from Arctic methane on near-term climate evolution. That economic modeling study was based on an Arctic methane release scenario proposed in an earlier paper by Shakhova (2010). In PNAS, Miller et al (2013) find that the United States may be emitting 50-70% more methane than we thought. So where does this leave us?
[Read more…] about Arctic and American Methane in Context