Monday, August 9, 2010

Update 2: Mt Everest melting! But who says it's so?

COMMENT: ABC's use IPCC AR4 WGII report Table 10.2 to back up claims made in a brief report on Mt Everest that stated "Studies show temperatures are rising faster at Mount Everest than in the rest of South Asia"  has thrown up some interesting issues. Most of these are covered at the Watts Up With That post: Himalayan warming – pulling another thread from IPCC’s fragile tapestry. Here's a summary:
1. Table 10.2 indicates that warming in the Himalaya is 0.09º C.yr-1 however warming citing for Si Lanka is 2°C increase per year in central highlands. Clearly ABC's claim doesn't add up. 
2. IPCC provide the incorrect reference to back their figure for the Himalayas. They cite two conference papers and one peer reviewed paper that related to precipitation, not temperature. The correct reference is found to be: Shrestha, Arun B.; Wake, Cameron P.; Mayewski, Paul A.; Dibb, Jack E., 1999. Maximum Temperature Trends in the Himalaya and Its Vicinity: An Analysis Based on Temperature Records from Nepal for the Period 1971–94. Journal of Climate, 9/1/99, Vol. 12 Issue 9 pp:2775-2786.
3. The references for the Sri Lankan Temperatures are not from peer reviewed journals, they relate to precipitation, not temperature.
4. The figure quoted for the Himalaya is the winter trend, not the annual trend. The annual trend is 0.057 º C.yr-1.
5. The highest annual trend for Nepal cited in Shrestha et al., 1999 is 0.09º C.yr-1 for the Trans-Himalaya (an area that excludes Mt Everest).
5. The basis of the Himalayan trends (Shrestha et al 1999) is just 6 weather stations,. The average trend of 5 of these stations dating back to the 1960s is (Max/Min) 0.013º C.yr-1, much less than the 0.057º C.yr-1. All five of these stations are located in the eastern Himalaya. There are problems with use of Kriging method to obtain regional trends.
6. The trend cited for Sri Lankan was brought up in the review of IPCC AR4 WGII:
WUWT reader Justcherrypicked finds:
Timeline:First Order Draft, 10.2.2 Observed climate trends and variability, Table 10.2 does not have a “change in temperature” entry for Sri Lanka, but does have entries for “Change in Precipitation”, and “References”. Which contain, “Increase trend in February and decrease trend in June” and “Chandrapala and Fernando, 1995; Chandrapala, 1996″ respectfully. Clearly, the two references relate to changes in precipitation, not temperature.

The missing entry is noted by Dr. Basnayake in FOD Expert Review Comments. He states:
“”Table 10.2″ under Sri Lanka -change in temperature “minimum and maximum temperatures have been increasing during tthe last centurary. 0.016 C increase per year during 1961-90 period over the entire country. 2.0 C increase per century over the central highlands.” under the references “Basnayake, B.R.S.B. et al 2002″”
. Note he said 2.0 C per century.
Dr. Basnayake’s comments are accepted by the lead authors and is then included in the Second Order Draft (SOD) as
“0.016°C increase per year between 1961-90over entire country, 2°C increase per year in central highlands”
Note they changed century to year, and left out the reference as well.
The error is picked up by Xiuqi Fang during the SOD expert review comments ,
“table 10.2. Check the temperature increasing rate in Sri Lanka. 2C increase per year is too high
(Xiuqi Fang, Beijing Normal University)”

, to which the LA responds “Table entries corrected”. Clearly they are not.
Sadly, Dr. Basnayake does not seem to be involved with the SOD as no reviewer comments for him exist.
Clearly, the IPCC statement “2.0 C increase per year” is an error that was pointed out and ultimately ignored. Additionally, the claim is without a citation.
Both ABC and IPCC have some explaining to do. We have passed this on to the IPCC for comment. 

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