cc: Simon Mason <simonatXYZxyz.columbia.edu>
date: Fri Feb 27 12:18:00 2009
from: Phil Jones <p.jonesatXYZxyz.ac.uk>
subject: Re: temperature specialist
to: Madeleine Thomson <mthomsonatXYZxyz.columbia.edu>
I've looked at this paper and it only looks at temperature and precipitation
data for the period 1966-1995. This paper is the one you gave me the link
for. If you meant to attach another, then I have not got it.
I don't have access to papers (26-28) which may use longer paper.
If though they use ref 34 or a more recent version (attached) then
there is much infilling of data in CRU TS 2.1 in much of Africa. Ref 34
and the attached shouldn't be relied on for long-term trends when
there is little available data in early decades of the 20th century.
If there is no observational data then the gridded reduces to putting
in the average temperature and rainfall for the 1961-90 period.
Simon will know what I'm talking about!
At 14:03 25/02/2009, Madeleine Thomson wrote:
I was given your name as a specialist in temperature analysis in Africa and am I am
writing to you to ask if you could share some of your knowledge on temperature and help
me better understand whether or not there is evidence of warming trends in the East
African highlands over the last century. My question relates to the discussions in the
literature over the last few years re the role that temperature increases may have
played in the observed increases in malaria epidemics in Kenya in particular (Kericho)
I am not trying to further the question - has climate change resulted in increases in
malaria (for which there is already an extensive literature) but rather try and
understand the importance or otherwise of a paper by Simon Hay and colleagues from
Oxford (Meteorologic Influences on Plasmodium falciparum Malaria in the Highland Tea
Estates of Kericho, Western Kenya Nature 2002;415:905-9 -
http://origin.cdc.gov/ncidod/EID/vol8no12/pdfs/02-0077.pdf) in which they analysed
meteorological data from 1901 to 1995 for four highland sites where malaria cases are on
the rise in East Africa
Kericho in western Kenya, Kabale in south-western Uganda, Gikonkko in southern Rwanda,
and Muhanga in northern Burundi. For each month, the researchers determined the average
temperature, as well as the average minimum and maximum temperature, rainfall and vapour
After analysing the 95-years' worth of data, the team found no significant shifts in
temperature or vapour pressure at any of the four sites. Rainfall had increased at only
The results of this paper were presented at a recent meeting with the statement that
there is no evidence for warming in East Africa over the last century. Is this really
the case - that there no evidence of a warming trend generally in East Africa - or
specifically at these sites.
I have seen scattered reports in the literature suggesting that there have been strong
warming trends over this time period but have yet to find a consolidated analysis. In
particular I am interested in trends in minimum temperature which are likely to be most
relevant to the malaria problem. I attach the paper of interest for your reference.
I look forward to your reply.
Madeleine C. Thomson Ph.D.
Senior Research Scientist
Director Impacts Research
Chair Africa Regional Programme
International Research Institute
for Climate and Society
The Earth Institute at
Palisades, 10964 New York
Tel: 1 845 680 4413
Fax: 1 845 680 4864
The IRI is a PAHO-WHO Collaborating Centre for Climate Sensitive Diseases
Prof. Phil Jones
Climatic Research Unit Telephone +44 (0) 1603 592090
School of Environmental Sciences Fax +44 (0) 1603 507784
University of East Anglia
Norwich Email p.jonesatXYZxyz.ac.uk