cc: slocke@ucsusa.org date: Fri, 30 Oct 1998 14:05:02 -0500 from: Molly_Smith@edf.org subject: Re: Follow-up to conversation with Adam Markham to: Mike Hulme From: Molly Smith@EDF on 10/30/98 02:05 PM Subject: Re: Follow-up to conversation with Adam Markham Thanks! I'll add the second two spots to our list, and we'll re-think our precipitation ideas. There is a chance that someone else from our group, Sharon Locke, may contact you to further discuss precipitation and droughts. I will also check out the Scientific American article you suggest. Molly From: Mike Hulme on 10/30/98 05:38 PM GMT To: Molly Smith cc: Subject: Re: Follow-up to conversation with Adam Markham Molly, To take your three points: 1. Southern African rainfall. Avoid this one - and indeed avoid pretty much all climate indicators related to precipitation. The large natural variability of precip. makes it very hard for a human-induced climate change trend to be picked up. 2. The CET daily temperature series are fine. Cold days are with mean temperature (i.e., average of day and night) below zero Celsius and hot days are with Tmean above 20degC. The records are homogenous to 1772. 1995 had the most hot days with 26 (1961-90 average is only about 4). 3. Your wording is accurate although I would replace 'JFM' with 'January to March' And if you're looking for more climate indicators try the following article in Scientific American: Karl,T.R., Nicholls,N. and Gregory,J. (1997) The coming climate Scientific American, May, 54-59. Regards, Mike At 14:10 27/10/98 -0500, you wrote: > >From: Molly Smith@EDF on 10/27/98 02:10 PM > >Subject: Follow-up to conversation with Adam Markham > >Hello: > >I am a researcher at the Environmental Defense Fund who is working on a >project with Adam Markham and others to compile a list of areas around the >world where there is evidence that global climate change is already >starting to occur. I believe Adam spoke to you not too long ago about this >project and that he gathered from you a list of additional trends that >could be used. I am writing to follow-up on that conversation and get a >few more details on the information you gave Adam. To summarize the >intentions of our project -- we woud like to create a world map that points >out the locations of these trends and events that give evidence in support >of the claim that climate change is already beginning to occur. Each site >would be accompanied by a 1-2 sentence blurb that summarizes the >trend/event and puts it in context. In order to include a point on our >map, it must be verified by a reliable source (i.e. peer-reviewed article >or expert on the matter), and it must be heavily climate influenced. If >the trend is only slightly due to climate and primarily due to outside >factors (i.e. Sea level rise in New Orleans which is mainly due to geologic >subsidence), we will not include the site, or possibly will include it with >an explanation of the non-climate factors(s). > >The first question I have is in regards to your information about southern >Africa and its recent period of rainfall deficeit. I read the Climatic >Change and Southern Africa report you wrote for WWF and am not sure what >your opinion is on whether this two-decade dry period is significant enough >to attribute it to a longer trend. I would also like your opinion on how >much of that drying trend can be blamed on climatic changes that have >already begun to occur. Does the occurrence of a wet year in 1995/96 >lessen the claim that the drier period was due to a changing climate? What >sort of blurb would be accurate for our pruposes? > >Another trend that I have questions about is the increase in hot days and >decrease in cold days in central England since 1772. The blurb I have is >as follows: > >"Central England ? RISING TEMPERATURES: The number of cold days per year >have declined in central England since 1772, while the number of hot days >per year have increased over that same period. Cold days have declined >from 15 to 20 days per year at the beginning of the record down to 10 days >per year in this century. The number of hot days have increased at a >slightly lower rate with the last decade averaging nearly 8 hot days per >year, the highest number on record (Mike Hulme, pers. comm.)" > >However, what temperatures define "cold" and "hot"? Is the information >quoted properly in this blurb? Do all of the records go back to 1772? >What year had the most # of hot days ever? > >The last trend I merely would like you to confirm the wording and check the >accuracy: > >"Southern England ? EARLIER SPRING: Oak trees (Quercus robur) have been >leafing earlier and earlier over the past 41 years in response to >increasing JFM temperatures at a rate of 5 to 6 days per 1C of warming. >The four earliest leafing dates in the last 41 years have all occurred in >the last decade (Mike Hulme, pers. comm.)" > >I appreciate your assistance on these questions and thank you in advance >for your time. We are trying to gather all of the information for our map >by the end of the month and therefore would appreciate a response as soon >as you get the chance. If you have any additional suggestions or ideas, >please feel free to pass those along as well. > >Thank you again for your help! > >Molly Smith >========================== >Environmental Defense Fund >257 Park Avenue South >New York, NY 10010 USA >tel: (212) 505-2100 >fax: (212) 505-2375 >e-mail: molly_smith@edf.org > > >