From: P.Jones@uea.ac.uk To: trenbert@ucar.edu Subject: Re: Climate Date: Wed, 17 Sep 2008 16:39:07 +0100 (BST) Cc: Wibjörn Karlén , "Phil Jones" Wibjorn, I'm in Athens at the moment. Unless you're referring specifically to the Arctic the temperature curves in IPCC Ch 3 all include the oceans. Fennoscandia is just a small part of the NH. When I'm back next week, I'll be able to calculate the boxes that encompass Fennoscandia, so you can compare with this region. As you're aware Anders did lots of the update work in 2001-2002 and he included all the NORDKLIM data. I can send you a list of the Fennoscandian data if you want - either the sites used or their data as well. I guess you're attachments are in your direct email, which I come to later. One final thing - we are getting SST data in from some of the new sea-ice free parts of the Arctic. We are not using these as we've yet to figure out how to as we don't have normals for these 'mostly covered by sea ice in the 1961-90' areas. Cheers Phil > Hi Wibjorn > It appears that your concern is mainly with the surface temprature record, > and my co lead author in IPCC, Phil Jones, is best able to address those > questions. However the IPCC only uses published data plus their > extensions and in our Chapter the sources of the data are well documented, > along with their characteristics. I offer a few more comments below (my > comments are limited as I am on vacation and away from my office). > > >> >> >> Uppsala 17 September 2008, >> >> >> >> Dear Kevin, >> >> >> >> In short, the problem is that I cannot find data supporting the >> temperature >> curves in IPCC and also published in e.g. Forster, P. et al. 2007: > Assessing uncertainty in climate simulation. Nature 4: 63-64. >> >> >> >> In attempts to reconstruct the temperature I find an increase from the > early >> 1900s to ca 1935, a trend down until the mid 1970s and so another > increase >> to about the same temperature level as in the late 1930s. >> >> >> >> A distinct warming to a temperature about 0.5 deg C above the level 1940 >> is >> reported in the IPCC diagrams. I have been searching for this recent > increase, which is very important for the discussion about a possible > human >> influence on climate, but I have basically failed to find an increase >> above >> the late 1930s. >> > > This region, as I am sure you know, suffers from missing data and large > gaps spatially. How one covered both can greatly influence the outcome. > In IPCC we produce an Arctic curve and describe its problems and > character. In IPCC the result is very conservative owing to lack of > inclusion of the Arctic where dramatic decreases in sea ice in recent > years have taken place: 2005 was lowest at the time we did our assessment > but 2007 is now the record closely followed by 2008. Anomalies of over 5C > are evident in some areas in SSTs but the SSTs are not established if > there was ice there previously. These and other indicators show that > there is no doubt about recent warming; see also chapter 4 of IPCC. > >> >> >> In my letter to “Klass V” I included diagram showing the mean annual > temperature of the Nordic countries (1890-ca 2001) presented on the net > by >> the database NORDKLIM, a joint project between the meteorological > institutes >> in the Nordic countries. Except for Denmark, the data sets show an >> increase >> after the 1970s to the same level as in the late 1930s or lower. None > demonstrates the distinct increase IPCC indicates. The trends of these 6 > areas are very similar except for a few interesting details. >> >> > > Results will also depend on the exact region. > >> >> I have in my studies of temperatures also checked a number of areas > using >> data from NASA. One, in my mind interesting study, includes all the 13 > stations with long and decent continuously records north of 65 deg N. > The >> pattern is the same as for the Nordic countries. This diagram only shows > 11-yr means of individual stations. A few stations such as Verhojansk > and >> Svalbard indicate a recent mean 11-year temperature increase up to 0.5 > deg >> C >> above the late 1930s. Verhojansk, shows this increase but the > temperature >> has after the peak temperature decreased with about 0.3 deg C during the > last few years. The majority of the stations show that the recent > temperatures are similar to the one in the late 1930s. >> >> >> >> In preparation of some talks I have been invited to give, I have > expanded >> the Nordic area both west and east. The area of similar change in > climate >> is >> vast. Only a few stations near Bering Strait deviates (e.g. St Paul, > Kodiak, >> Nome, located south of 65 deg. N). >> >> >> >> My studies include Africa, a study which took me most of a summer > because >> there are a large number of stations in the NASA records. I found 11 > stations including data from 1898-1975 and 16 stations including > 1950-2003. >> The data sets could in a convincing way be spliced. However, I noticed >> that >> some persons were not familiar with “splicing” technique so I have >> accepted >> to reduce the study to the 7 stations including data from the whole > period >> between 1898-2003. The results are similar as to the spiced data set and > also, surprisingly similar to the variability of the Nordic data. > Regression >> indicates a minor (if any) decrease in temperature (I have used all > stations >> independent of location, city location or not). >> > Africa is notorious for missing and inaccurate data and needs careful > assessment. >> >> >> Another example is Australia. NASA only presents 3 stations covering the > period 1897-1992. What kind of data is the IPCC Australia diagram based > on? >> If any trend it is a slight cooling. However, if a shorter period > (1949-2005) is used, the temperature has increased substantially. >> >> > > The Australians have many stations and have published more detailed maps > of changes and trends. > > >> >> There are more examples, but I think this is much enough for my present > point: >> >> >> >> How has the laboratories feeding IPCC with temperature records selected > stations? >> > See our chapter and the appendices. >> >> >> I have noticed that major cities often demonstrate a major urban effect > (Buenos Aires, Osaka, New York Central Park, etc). Have data from major > cities been used by the laboratories sending data to IPCC? Lennart > Bengtsson and other claims that the urban effect is accounted for but > from >> what I read, it seems like the technique used has been a simplistic >> > > Major inner cities are excluded: their climate change is real but very > local. > >> >> >> Next step has been to compare my results with temperature records in the > literature. One interesting figures is published by you in: >> >> >> >> Trenberth, K., 2005: Uncertainty in Hurricanes and Global Warming. >> Science >> 308: 1753-1754. >> >> >> >> As you obviously know, the recent increase in temperature above the > 1940s >> is >> minor between 10 deg N and 20 deg N and only slightly larger above the > temperature maximum in the early 1950s. Booth the increases in > temperature >> in the 1930s and in the 1980s to 1990s is of similar amplitude and > similar >> steepness, if any difference possibly slightly less steep in the > northern >> area than in the southern (the eddies slow down the warm water >> transport?). >> Your diagram describes a limited area of the North Atlantic because you >> are >> primarily interested in hurricanes. The complexity of sea surface > temperature increases and decreases is seen in e.g. Cabanes, C, et al. > 2001 >> (Science 294: 840-842). >> > > As we discuss, there is a lot of natural variability in the North Atlantic > but there is also a common component that relates to global changes. See > my GRL article with Shea for more details. > Trenberth, K. E., and D. J. Shea, 2006: Atlantic hurricanes and natural > variability in 2005. Geophys. Res. Lett., 33, L12704, > doi:10.1029/2006GL026894. > >> >> >> One example of sea surface temperature is published by: >> >> >> >> Goldenberg, S.B., Landsea, C.W., Mestas-Nuñez, A.M. and Gray, W.M., > 2001: >> The recent increases in Atlantic hurricane activity: causes and >> implications. Science 293: 474-479. >> >> >> >> Again, there is a marked increase in temperature in the 1930s and 1950s > (about 1 deg C), a decrease to approximately the level in the 1910s and > thereafter a new increase to a temperature slightly below the level in > the1940s. >> >> >> One example of published data not supporting a major temperature > increase >> during recent time is: >> >> >> Polyakov, I.V., Bekryaev, R.V., Alekseev, G.H., Bhatt,U.S., Colony, > R.L., >> Johnson, M.A., Maskshtas, A.P. and Walsh, D., 2003: Variability and > Trends >> of Air Temperature and Pressure in the Maritime Arctic, 1875–2000. > Journal >> of Climate: Vol. 16 (12): 2067–2077. >> >> >> >> >> He included many more stations than I did in my calculation of >> temperatures >> N 65 N, but the result is similar. It is hard to find evidence of a >> drastic >> warming of the Arctic. >> >> >> >> It is also difficult to find evidence of a drastic warming outside urban > areas in a large part of the world outside Europe. However the increase > in >> temperature in Central Europe may be because the whole are is urbanised > (see >> e.g. Bidwell, T., 2004: Scotobiology – the biology of darkness. Global > change News Letter No. 58 June, 2004). >> >> >> >> >> >> So, I find it necessary to object to the talk about a scaring > temperature >> increase because of increased human release of CO2. In fact, the warming > seems to be limited to densely populated areas. The often mentioned > correlation between temperature and CO2 is not convincing. If there is a > factor explaining a major part of changes in the temperature, it is > solar >> irradiation. There are numerous studies demonstrating this correlation > but >> papers are not accepted by IPCC. Most likely, any reduction of CO2 > release >> will have no effect whatsoever on the temperature (independent of how > expensive). >> > > You can object all you like but you are not looking at the evidence and > you need to have a basis, which you have not established. You seem to > doubt that CO2 has increased and that it is a greenhouse gas and you are > very wrong. But of course there is a lot of variability and looking at > one spot narrowly is not the way to see the big picture. > > >> >> >> In my mind, we have to accept that it is great if we can reduce the >> release >> of CO2 because we are using up a resource the earth will be short of in >> the >> future, but we are in error if we claims a global warming caused by CO2. >> > I disagree. >> >> >> I also think we had to protest when erroneous data like the claim that > winter temperature in Abisko increased by 5.5 deg C during the last 100 > years. The real increase is 0.4 deg C. The 5.5 deg C figure has been > repeated a number of times in TV-programs. This kind of exaggerations is > not >> supporting attempts to save fossil fuel. >> >> >> >> I have numerous diagrams illustrating the discussion above. I don’t >> include >> these in an e-mail because my computer can only handle a few at a time. > If >> you would like to see some, I can send them by air mail. >> >> >> >> I am often asked about why I don’t publish about my views. I have. Just >> one >> example of among 100 other I could select is: Karlén, W., 2001: Global > temperature forces by solar irradiation and greenhouse gases? Ambio > 30(6): >> 349-350. >> >> >> >> Yours sincerely >> >> >> >> Wibjörn >> >> >> >> Geografiska Annaler >> >> Professor em Wibjörn Karlén >> >> Department of Social and Economic Geography >> >> >> Geografiska Annaler Ser. A >> >> Box 513 >> >> SE-751 20 Uppsala >> >> SWEDEN >> >> >> >> Wibjorn.Karlen@kultgeog.uu.se >> > > I trust that Phil Jones may also respond > Regards > Kevin Trenberth > > > ___________________ > Kevin Trenberth > Climate Analysis Section, NCAR > PO Box 3000 > Boulder CO 80307 > ph 303 497 1318 > http://www.cgd.ucar.edu/cas/trenbert.html > > > >