It would be helpful if the IGBP (or some other group like Alan's, which has more capability to generate such an index better than most) also had a variability index that included volcanic eruption effects and El Nino/La Nina effects on at least global average temperature (in that we essentially can estimate these, or at least can get a good sense of them by correlation and fancier analyses of past observations); of course, a problem is that the two may not be completely independent. [I'd add in solar variations if I thought we understand them well enough to do, but in any case best estimate is that they are smaller--or at least smoother.]
And if one were clever, one might even do a short-term variation chart for the CO2 concentration (volcanic eruptions, by scattering light, are thought to temporarily enhance carbon uptake; ENSO can also have an effect, as can variations in fires), and they even might have a variability index for how volcanic eruptions and ENSO affect sea level (or ocean heat content). Finally, it is a bit surprising to me (and will be misleading later) that IGBP uses minimum summer sea ice cover as an index--when this goes to zero, it presumably will imply that there is no more change going on in the this component of the Earth system, which will be wrong. It seems to me they need to figure out some composite cryosphere index. The sea ice component might be the average annual fractional coverage of sea ice or sea ice volume--though that too could go to zero change in the future, but more distantly. Then add in mountain glacier and ice sheet components, with some weighting--or maybe make it total ice loss per year from Arctic sea ice, mountain glaciers, the ice sheets, and even permafrost. This would be equivalent to the energy going into melting all the ice, so one of the terms in the global energy balance (along with ocean heat uptake). Mike On 12/9/09 9:22 AM, "Alan Robock" <[email protected]> wrote: > Dear Ken, > > No. > > First, there was no eruption in 1996 that affected climate. And how can > you cherry-pick and choose the same year for El Chichón, whose effects > were largely masked by the huge El Niño that year, and choose the year > after the eruption for Pinatubo? Which is it? So your theory that > these data show beneficial effects from eruptions is wrong. > > Second, volcanic eruptions cause drought, ozone depletion, and loss of > direct solar power. So you have to take the good with the bad and > carefully evaluate all the effects. > > Alan > > Alan Robock, Professor II > Director, Meteorology Undergraduate Program > Associate Director, Center for Environmental Prediction > Department of Environmental Sciences Phone: +1-732-932-9800 x6222 > Rutgers University Fax: +1-732-932-8644 > 14 College Farm Road E-mail: [email protected] > New Brunswick, NJ 08901-8551 USA http://envsci.rutgers.edu/~robock > > > On Wed, 9 Dec 2009, Ken Caldeira wrote: > >> The IGBP has developed a "Climate Change Index": >> >> *The index gives an annual snapshot of how the planet?s complex systems ? >> the ice, the oceans, the land surface and the atmosphere - are responding to >> the changing climate. >> *...* >> **The index dips in just three years, 1982, 1992 and 1996 and looks >> effective at capturing major natural events that affect climate, and their >> knock-on effect on the planet. The dip in the curve in 1992 may have been >> caused by the massive Mount Pinatubo volcanic eruption in Indonesia in 1991. >> The eruption was large enough to affect temperature and sea level on a >> planetary scale. The other falls coincide with the El Chichon volcanic >> eruption in Mexico in 1982 and the volcanic eruption on the Caribbean island >> of Montserrat in 1996.* >> >> If the IGBP's "Climate Change Index" only shows improvements after large >> volcanoes, is the IGBP telling us something about the potential for >> intentional intervention in the climate system? >> >> >> ___________________________________________________ >> Ken Caldeira >> >> Carnegie Institution Dept of Global Ecology >> 260 Panama Street, Stanford, CA 94305 USA >> >> [email protected] >> http://dge.stanford.edu/DGE/CIWDGE/labs/caldeiralab >> +1 650 704 7212; fax: +1 650 462 5968 >> >> >> >> >> ---------- Forwarded message ---------- >> From: Virginie Le Saout <[email protected]> >> Date: Wed, Dec 9, 2009 at 6:30 PM >> Subject: IGBP Climate Change Index >> To: >> >> >> >> >> *IGBP Climate-Change Index * >> >> * * >> >> *EMBARGO: 9 December 09:00 CET (08:00 GMT, 03:00 EST, US)* >> >> * * >> >> * * >> >> *Press conference: UNFCCC - COP15,* *Asger Jorn Room, Hall H, Bella Center, >> Copenhagen.* >> >> * * >> >> >> >> Some people still question whether Earth?s climate is changing as rapidly >> and profoundly as the majority of climate scientists suggest. But, what if >> the complexity of the Earth?s climate were distilled down to one number, in >> the same way that the Dow Jones Index condenses volumes of data into a >> single figure? What, then, would be the general trend? >> >> >> >> The IGBP Climate-Change Index is a first attempt to do just that. It brings >> together key indicators of global change: carbon dioxide, temperature, sea >> level and sea ice. The index gives an annual snapshot of how the planet?s >> complex systems ? the ice, the oceans, the land surface and the atmosphere - >> are responding to the changing climate. The index rises steadily from 1980 ? >> the earliest date the index has been calculated. The change is unequivocal, >> it is global, and, significantly, it is in one direction. The reason for >> concern becomes clear: in just 30 years we are witnessing major >> planetary-scale changes. >> >> >> >> The index dips in just three years, 1982, 1992 and 1996 and looks effective >> at capturing major natural events that affect climate, and their knock-on >> effect on the planet. The dip in the curve in 1992 may have been caused by >> the massive Mount Pinatubo volcanic eruption in Indonesia in 1991. The >> eruption was large enough to affect temperature and sea level on a planetary >> scale. The other falls coincide with the El Chichon volcanic eruption in >> Mexico in 1982 and the volcanic eruption on the Caribbean island of >> Montserrat in 1996. If this link proves robust, the index is an excellent >> visual tool to show how external events can have rapid planetary-scale >> effects. Of course, the overall direction of change ? a climbing cumulative >> index ? highlights the extent human activities are having on the planet?s >> climate system. >> >> >> >> Date >> >> Climate-change index >> >> Cumulative change in the index >> >> 1980 >> >> 24 >> >> 24 >> >> 1981 >> >> 37 >> >> 61 >> >> 1982 >> >> -19 >> >> 42 >> >> 1983 >> >> 39 >> >> 81 >> >> 1984 >> >> 9 >> >> 90 >> >> 1985 >> >> 8 >> >> 98 >> >> 1986 >> >> 5 >> >> 103 >> >> 1987 >> >> 31 >> >> 134 >> >> 1988 >> >> 33 >> >> 167 >> >> 1989 >> >> 18 >> >> 185 >> >> 1990 >> >> 34 >> >> 218 >> >> 1991 >> >> 10 >> >> 228 >> >> 1992 >> >> -25 >> >> 203 >> >> 1993 >> >> 14 >> >> 217 >> >> 1994 >> >> 21 >> >> 237 >> >> 1995 >> >> 47 >> >> 284 >> >> 1996 >> >> -6 >> >> 278 >> >> 1997 >> >> 35 >> >> 313 >> >> 1998 >> >> 37 >> >> 349 >> >> 1999 >> >> 15 >> >> 365 >> >> 2000 >> >> 7 >> >> 372 >> >> 2001 >> >> 19 >> >> 391 >> >> 2002 >> >> 34 >> >> 425 >> >> 2003 >> >> 28 >> >> 454 >> >> 2004 >> >> 15 >> >> 468 >> >> 2005 >> >> 43 >> >> 512 >> >> 2006 >> >> 29 >> >> 541 >> >> 2007 >> >> 33 >> >> 574 >> >> >> >> >> >> The idea came about when several IGBP scientists including Steven Running, >> IGBP >> executive director Sybil Seitzinger, former IGBP director Kevin Noone, Kathy >> Hibbard, Mark Stafford Smith, Peter Cox, Suzi Kerr and Pierre >> Friedlingsten realised >> that the way various global datasets are reported throughout the year may be >> confusing. It is uncoordinated, there are a variety of unfamiliar units, and >> natural variability sometimes masks a trend. >> >> >> >> Professor Seitzinger says, ?We felt people outside global-change research >> are not clear about the scale of the changes scientists are witnessing. The >> index is a response to these concerns.? >> >> >> >> Why those four metrics? Professor Steven Running from the University of >> Montana says, ?The iconic Mauna Loa atmospheric CO2 concentration was >> obvious. Global air temperature is already widely reported at the end of >> each calendar year, so that was a logical choice too. >> >> >> >> ?We needed an oceanic measure and chose sea-level rise because the impact is >> global and of high public interest. The fourth metric concerns the >> cryosphere. Growing concern about the rate of loss of summer sea-ice in the >> Arctic led us to choose this metric. This parameter broadly represents the >> Earth system and it is interesting the summer sea-ice extent is shrinking >> much faster than models predicted five, ten years ago,? said Professor >> Running, a lead author on the Intergovernmental Panel on Climate Change >> Fourth Assessment Report. >> >> >> >> In the future, other variables could be added. ?We did not identify any good >> land surface variable, because no good standard exists,? says Professor >> Running. ?But some day we may have annual albedo or land-cover change.? >> >> >> >> Each parameter is normalised between -100 and +100. Zero is no annual >> change. One hundred is the maximum-recorded annual change since 1980. The >> normalised parameters are averaged. This gives the index for the year. The >> value for each year is added to that of the previous year to show the >> cumulative effect of annual change. >> >> >> >> Professor Running says, ?Some of us thought we?d need a five-year rolling >> average to help dampen fluctuations and to elucidate core trends. But when >> we first produced the index it was obvious this was unnecessary: the index >> highlights the trend extremely effectively.? >> >> >> >> The index has been developed with input from a large number of scientists >> involved in global-change research. Some scientists questioned whether >> atmospheric carbon dioxide levels should be included. They argued that, >> because carbon dioxide drives changes in the three other parameters, it >> should be excluded. But others argue that it is human activity that is the >> external forcing agent. Additionally, as atmospheric carbon dioxide levels >> fluctuate, this in turn affects the effectiveness of other major carbon >> sinks: the oceans and the land. So, given the size of its influence on the >> climate, the arguments to include atmospheric carbon dioxide levels outweigh >> arguments for exclusion. Recalculating the index without carbon dioxide >> shows that carbon dioxide does not dominate the trend. >> >> >> >> IGBP scientists are discussing developing other indices relating to global >> change such as an index including land-use, fisheries exploitation, >> population, fire and extreme events, as well as backdating the new index. >> >> >> >> The index will be updated annually. >> >> >> >> See www.igbp.net for more information >> >> Notes for editors >> >> >> Seven images are available. >> >> >> >> Contact >> >> >> >> Owen Gaffney >> >> Director of communications >> >> International Geosphere-Biosphere Programme >> >> Email: [email protected] >> >> Tel: +46 86739556 >> >> Mob: +46 730208418 >> >> Skype: owengaffneyigbp >> >> Website: www.igbp.net >> >> >> >> >> >> >> >> *International Geosphere-Biosphere Programme* >> >> The International Council for Science (ICSU) formed the International >> Geosphere-Biosphere Programme (IGBP) in 1987 in recognition that climate >> change is one part of a much larger challenge: global change. IGBP's vision >> is to provide scientific knowledge to improve the sustainability of the >> living Earth. IGBP involves researchers from 74 nations and is based at the >> Royal Swedish Academy of Sciences. >> >> >> >> www.igbp.net >> >> -- >> >> You received this message because you are subscribed to the Google Groups >> "geoengineering" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]. >> For more options, visit this group at >> http://groups.google.com/group/geoengineering?hl=en. >> >> >> > > -- > > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/geoengineering?hl=en. > > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
