The entire CRUTEM3 database of station temperature measurements has just been released. This comes after a multi-year process to get permissions from individual National Weather Services to allow the passing on of data to third parties and from a ruling from the UK ICO. All the NWSs have now either agreed or not responded (except for Poland which specifically refused). Since the Polish data is a such a small fraction of the globe (and there are a few Polish stations in any case via RBSC or GCOS), this doesn’t make much difference to hemispheric means or regional climate. These permissions were obtained with help from the UK Met Office (who have also placed the station data on their website in a slightly different format) and whose FAQ is quite informative.

A new piece  (open access) published in the Proceedings of the National Academy of Sciences assesses the potential impact of climate change on penguin populations in Antarctica. It could provide an excellent reading in the science section of a climate change course as a case study.  Among the take-aways from the study:

1. While it had been hypothesized that the populations of Adelie penguins, which favor pack-ice habitat in winter in the West Antarctic Peninsula and Scotia Sea, would decline in the face of warming, while ice-avoiding chinstrap penguins would see population increases, empirical evidence shows that both have declined more than 50% in the last 30 years in the South Shetland Islands, and 75% in the South Sandwich Islands;
2. The primary reasons that both species have declined is a massive drop in krill populations (with density declining  80% from the mid-1970s and a 38-81% decline in biomass). This is attributable to increasing temperatur5es, and consequent reductions in sea ice necessary to sustain large krill populations, and increasing competition from recovering seal and whale populations;
3. The decline in the reproductive capacity of the krill population, along with declines in sea ice, may ensure further declines in food resources for penguins and other predators in the West Antarctic Peninsula;
4. Krill catches in the West Antarctic and South Sandwich Islands have increased four fold in the past  ten years, and may expand further given the Marine Stewardship Council’s recent certification of one company’s krill fishing operations as sustainable, and introduction of new products, e.g. Omega-3 krill oil.

This study is another cautionary tale in the realm of climate science; as the study concludes, a species that was believed to be a “winner” as a consequence of climate chang’may be among the most vulnerable species affected by a warming climate.”

Good statistic for climate science lecture: Atmospheric levels of carbon dioxide are currently increasing at an annual rate of 0.5%, “200 times faster than any changes that occurred during the last eight glacial cycles.” Albright, et al., Ocean Acidification Compromises Recritment Success of the Threatened Caribbean Coral Acropora Palmata, PNAS Early Edition, 10.1073/pnas.1007273107 (2010).

An excellent new student reading for the science section of climate courses is a piece in Science looking at observational evidence from Earth’s past to project potential warming over the course of this century and beyond, Kiehl, Lessons from the Past, 331 Science 158-59 (2011).

Among the key take-aways:

1. Atmospheric carbon dioxide concentrations have reached 390ppmv;
2. The study reconstructed atmospheric concentrations of carbon dioxide throughout history and concluded the following the last time that concentrations reached levels projected by the end of this century under business as usual projections (900-1100 ppmv) would produce the following results:
   • When carbon dioxide concentrations reached 1000ppmv 35 million years ago, tropical to subtropical sea surface temperatures were in the range of 35-40C, vs. present day temperatures of 30C, while sea surface temperatures at polar latitudes in the South Pacific were 20-25C vs. modern temperatures of 5C;
   • Net radiative forcing during this period was 6.5-10 Wm-2
   • Global annual mean temperature 35 million years ago was 31C vs. 15C during pre-industrial times. This indicates that the climate feedback factor (the ratio of change in surface temperature to radiative forcing) may be as much as 4x greater than predicted by climate models
3. Reduction of carbon dioxide to lower levels of the recent past took tens of millions of years; by contrast, the burning of fossil fuels will return Earth to higher levels within centuries;
4. Earth’s concentration of carbon dioxide is rapidly rising to levels not seen in 30-100 million years, with potentially very large amplification of warming via climatic feedbacks.

 

FYI. The study can be found at: wires.wiley.com/climatechange.

Troposphere Is Warming Too, Decades Of Data Show

Date: 16-Nov-10
Country: USA
Author: Deborah Zabarenko

Not only is Earth’s surface warming, but the troposphere — the lowest level of the atmosphere, where weather occurs — is heating up too, U.S. and British meteorologists reported on Monday.

In a review of four decades of data on troposphere temperatures, the scientists found that warming in this key atmospheric layer was occurring, just as many researchers expected it would as more greenhouse gases built up and trapped heat close to the Earth.

This study aims to put to rest a controversy that began 20 years ago, when a 1990 scientific report based on satellite observations raised questions about whether the troposphere was warming, even as Earth’s surface temperatures climbed.

The original discrepancy between what the climate models predicted and what satellites and weather balloons measured had to do with how the observations were made, according to Dian Seidel, research meteorologist for the U.S. National Oceanic and Atmospheric Administration.

It was relatively easy to track surface temperatures, since most weather stations sat on or close to the ground, Seidel said by telephone from NOAA’s Air Resources Laboratory in Silver Spring, Maryland, outside Washington.

Measuring temperature in the troposphere is more complicated. Starting in the late 1950s, scientists dangled weather instruments from big balloons, with the data sent back to researchers by radio transmission as the balloons rose through the six miles of the troposphere.

BALLOONS AND SATELLITES

The first satellite data on troposphere temperature was gathered in 1979, but neither weather balloons nor these early satellite weather observations were accurate measures of climate change, Seidel said.

“They’re weather balloons and weather satellites, they’re not climate balloons and climate satellites,” she said. “They’re not calibrated precisely enough to monitor small changes in climate that we expect to see.”

When the 1990 study was published, showing a lack of warming in the troposphere especially in the tropics, it prompted some to question the reality of surface warming and whether climate models could be relied upon, NOAA said in a statement.

This latest paper reviewed 195 cited papers, climate model results and atmospheric data sets, and found no fundamental discrepancy between what was predicted and what is happening in the troposphere. It is warming, the study found.

This study is one of several published this year pushing back against those who doubt the reality of climate change and the role human activities play in it.

Scientists at NOAA, the United Kingdom Met Office and the University of Reading contributed to the paper, published on Monday in Wiley Interdisciplinary Reviews – Climate Change, a peer-reviewed journal.

International climate change talks are set to start on November 29 in Cancun, Mexico, but prospects for a global deal to curb greenhouse emissions are considered slim.

The U.S. National Oceanic & Atmospheric Administration’s 2010 Arctic Report Card is an extremely good source of information on Arctic climatic trends. The site also includes an abundance of very good graphics.

Among the findings in the report:

1. The first half of 2010 saw a near record pace of temperature anomalies in the region, with anomalies of over 4C in northern Canada; but this could moderate for the rest of the year due to La Niña influences.
2. Winter 2009-2010 showed a new connectivity between mid-latitude extreme cold and snowy weather events and changes in the wind patterns of the Arctic; the so-called Warm Arctic-Cold Continents pattern;
3. The 2010 sea-ice minimum is the third-lowest recorded since 1979, surpassed only by 2008 and the record low in 2007; The March 2010 ice extent was 15.1 million km2, about 4% less that the 1979–2000 average of 15.8 million km.;
4. There has been a substantial loss in the oldest ice types within the Arctic Basin in recent years compared to the late 1980s;
5. A combination of low winter snow accumulation and warm spring temperatures created a new record low spring snow cover duration over the Arctic in 2010, since satellite observations began in 1966;
6. Greenland climate in 2010 is marked by record-setting high air temperatures, ice loss by melting, and marine-terminating glacier area loss;
7. There is also evidence that the effect of higher air temperatures in the Arctic atmosphere in fall is contributing to changes in the atmospheric circulation in both the Arctic and northern mid-latitudes. Winter 2009-2010 showed a link between mid-latitude extreme cold and snowy weather events and changes in the wind patterns of the Arctic, related to a phase of the Arctic Oscillation.

New web pages explaining the science behind climate change have been launched by Professor Sir John Beddington, Government Chief Scientific Adviser for the U.K.’s Government Office for Science. The online resource, produced with the support of Met Office scientists, presents an overview of some of the important areas of climate science, explaining the issues, evidence and principles behind key points to help people understand the science of climate change. This is a concise overview of climate science that would be appropriate for undergraduate or graduate students.