cc: jhansen@giss.nasa.gov, p.jones@uea.ac.uk, bbaker@ncdc.noaa.gov, tkarl@ncdc.noaa.gov date: Wed, 15 Mar 2000 09:18:20 -0500 from: rquayle@ncdc.noaa.gov subject: Re: Surface Temperatures and Solar Activity to: Jacques Beckers (See attached file: CARDS_58_98.doc) Jim, Phil: I will be retiring June 3 .. gonna take a summer off for the 1st time in adulthood. As a parting shot (tho I may get back in the fray a bit if my old understudy Tom Karl needs some help), I ran off a few graphics on unadjusted CARDS data ... attached. Already sent them to Dave Parker. They are quite interesting, I think. And 100% independent of either LATs or SSTs. Rob home email: 110273.1027@compuserve.com Jacques: You asked: (i) What is the cause of the, in my mind, peculiar annual variation in global surface temperature (item 9 above)? It is (as you suggest) mainly the asymmetry of the land masses (more seasonal, more in NH) and oceans (less seasonal, more in SH) that induces the seasonal cycle in global surface temperatures. (ii) Has anyone else to your knowledge looked into similar relations between solar activity and global surface temperatures? Yes ... in fact this was the reason that we (NCDC) originally keypunched the World Weather Records data into punched cards in the early 1970s, tho the applications of the data have been far wider. The work was done by a group I headed at the time. The effort was funded by a personal grant of about $27,000 from science patron John Wolbach (affiliated with the Harvard Observatory). Since that time a great deal of work has been done on solar influences on global surface temperature, and the topic will be considered by the IPCC again I am sure. I believe it is now assumed that at least a portion of the global surface temperature variation is attributable to solar influences. To invert your argument somewhat, there is excess warming over and above the delta T of 1.9*ln(C/Co) that one would derive based only on CO2 concentration increasing from Co to C (Shine et al, 1990, Climate Change: The IPCC Scientific Assessment), and a portion of this is likely solar. (iii) what other mechanisms are being proposed to explain the global surface warming since 1880? Natural variability, feedbacks (particularly water vapor), aerosol pollution, oceanic circulation changes (natural and otherwise) are among several wild cards. IPCC is the global arbiter on these matters. (iv) Where do I find the best description related to the matters discussed above? IPCC documents, for openers. But a literature search would also be of value, including the AGU journal Geophysical Research Letters, and journals with Climate in the title. Note: You have said:" ... 1.5% increase in global surface temperature in January or about 4 C." This is not an apt characterization of temperature change for most discussions (tho it is OK when characterizing a segment of a range, which is what I assumed you meant). Rob Robert G. Quayle Chief, Climate Data Division National Climatic Data Center 151 Patton Ave. Asheville, NC 28801-5001 USA Voice: 828-271-4245 Fax: 828-271-4328 (or 4246) Internet: rquayle@ncdc.noaa.gov Jacques Beckers on 03/14/2000 06:57:55 PM To: Rob Quayle/NCDC cc: jhansen@giss.nasa.gov, p.jones@uea.ac.uk Subject: Surface Temperatures and Solar Activity Dear Robert Quayle, I am an astrophysicist working at the National Solar Observatory division at Sacramento Peak, New Mexico. The reason I am writing you relates to an article I saw in the NY Times a few weeks ago about a NRC Committee study on "Reconciling Observations of Global Temperature Change". I was fascinated with the apparent quality, over an extended period of time, of the land and ocean surface temperature observations and the question naturally arose in my mind whether they may contain the signature of the solar "constant" variations which we now know to exist. These luminosity changes amount to about 0.1% (lowest at solar minimum) and are closely related to the solar activity cycle. So I read the report of the NRC study, specifically chapter 6 on Surface Temperature Observations, read your paper in Geophysical Research Letters (volume 26, 333, 1999) to which it referred, and looked up your 1880 - 1999 data base on annual land surface (LAT) and ocean surface (SST) temperatures on the NCDC/NOAA web site. I then did a comparative analysis of these data with the solar activity record, using the Wolf sunspot number R as the activity measure. In this e-mail I summarize the results, and my request to you is to give me your reaction and to answer a number of questions which arose in my mind. I undertook the following steps in the manipulation of the sunspot and surface temperature data: (1) I took a running mean over 11 years. This removes quite effectively the 11 year sunspot cycle variation and showed the long term variation of solar activity. It smoothed of course the surface temperature measurements. These running means shows of course the gradual increase in LAT and SST over time with a plateau, or slight decrease, from1940 to 1975 referred to in your studies and in the NRC report. The running mean of R shows a similar behavior: a gradual increase over the 1880 - 1999 period except for a decrease from 1955 to 1970. The correlation over this period between LAT/SST and R is 75%/87% respectively. Even though this is very high, I am reluctant to conclude that the two are coupled. The result could be due to long term trends in two otherwise unrelated properties. (2) Two items may indicate, however, that there may be something to this long-term correlation: (i) the plateau/decrease in all quantities around the 1960's already mentioned, and (ii) the extrapolation of the relation to zero sunspot numbers which results in a temperature decrease of 0.7 C with respect to today's average surface temperature. One is reminded here of the Maunder Sunspot minimum (no sunspots)/Little Ice Age situation around 1600 when the estimated northern hemisphere temperature was 1 to 1. 5 degrees lower than today. That is two times as much, but then the time scale involved is much longer. (3) If one assumes the long-term correlation to be physically real, the question arises : Is there evidence of any other source of recent global heating since 1980? Removal of (the questionable) solar activity related term results in +0.40 +/- 0.16 C and +0.17 +/- 0.08 C for the LAT and SST respectively as compared to anomalies of +0.56 C and +0.29 C respectively from the NCDC/NOAA data (11 year running average centered on 1993). The evidence for remaining source(s) of surface heating therefore remain. (4) Then I subtracted the 11 year running mean from all data and looked for solar cycle related effects. (5) Both LAT and SST showed a positive correlation with the R values. That is the case for a zero time lag, but the correlation is largest when the R data are delayed by 1.55 years (1.3 years for LAT, 1.8 years for SST). The correlation is small: 9%/10% for LAT/SST. I have the impression , however that it is real from looking at subsets of the data. (6) Also the fact that there is this 1.55 year delay appears to agree with the 1.55 +/- 0.21 year at which the peak of the solar sunspot number precedes the middle of the solar activity cycle as defined by the activity minima (the sunspot number is highly skewed). From the limited amount of data we have (started in 1980) there is evidence that the solar "constant" cycle is centered on the solar activity minima. (7) If the solar cycle variation is real, the slope is such that a R cycle amplitude of 150 (as has been the case for recent solar cycle for which we have solar "constant" data) results in temperature amplitudes of 0.042 C/0.023C for LAT/SST respectively with lowest temperatures occurring at solar minimum. (8) Given a simple model of constant Earth albedo and emissivity and no other geophysical effects a (visible light) radiative energy in = (IR) radiative energy out would give for a 0.1% variation in the solar constant a 0.025% change in the Earth' temperature, or about 0.07 C, equal in sign and not too different from the values inferred under (7). (9) Encouraged by that I decided to examine the annual variations in LAT and SST. Since the Sun is closest to Earth in early January one expects about a 6% higher radiation input. Using the same argument as given under (8) one therefore expects a 1.5% increase in global surface temperature in January or about 4 C. Well, your data base shows a global temperature decrease of 9.1C/3.2 C for LAT/SST instead. Why is that? Does the larger land mass in the Northern hemisphere cause that? Is the origin in other geophysical effects? Anyway, that's where I am at this point. I need a reality check and I thought that you would be the best person to call on since I am using your data compilations on the global temperatures. I would very much appreciate receiving your reactions to all of this. Specific questions I have are: (i) What is the cause of the, in my mind, peculiar annual variation in global surface temperature (item 9 above)? (ii) Has anyone else to your knowledge looked into similar relations between solar activity and global surface temperatures? (iii) what other mechanisms are being proposed to explain the global surface warming since 1880? (iv) Where do I find the best description related to the matters discussed above? I would very much appreciate it if you would give me some of your time for a response! I copy Drs J.E. Hansen and P.D. Jones on this e-mail whose work was also referred to in the NRC report. I would appreciate receiving comments from them as well. With best regards, Jacques Beckers Astronomer National Solar Observatory/Sacramento Peak ********************************************** Jacques M. Beckers National Solar Observatory/NOAO P.O. Box 62 Sunspot, NM 88349 E-mail: jbeckers@noao.edu Phone: +1 505 434-7020 (work) +1 505 443-6005 (home Sunspot) +1 312 932-9250 (home Chicago) Fax: +1 505 434-7029 (work) +1 505 443-6005 (home Sunspot) +1 312 932-9251 (home Chicago) ********************************************** Attachment Converted: "c:\eudora\attach\CARDS_58_98.doc"