On Mon, Nov 30, 2009 at 2:33 PM, Sam <[email protected]> wrote: > > I'm saying you are contradicting yourself. > > As for NASA, anything from Hansen I don't trust. > > I don't know who this guy is but he has a pretty graph. > http://heliogenic.blogspot.com/2009/04/nasa-giss-data-stinks.html
I don't know who that guy is either but there are a couple of obvious problems with that graph. 1) it zeros out temperature data at 1940 but does not do the same for solar influx. If you want to compare the amplitude and direction of change, you have to have a common origin on your graph. If he had moved the scale of solar influx so that 1940 was zeroed out for that trend line, you'd see that 1940 to roughly 1956 (it looks like) would be way above the origin, unlike all the temperature trend lines. The covariance of solar influx with temperature change being the guys primary point, that is not something he wants to show in an obvious way. 2) One of the trend lines he includes and that he specifically pimps in the accompanying commentary is from National Geographic and ends in 1976. Since the rate of increasing in temperature has spiked dramatically since 1980, that is a very curious trend line to include. I don't know enough about the underlying data sets from the other trend lines to be sure, but I'm suspicious about including one proxied trend line for China and one raw trend line for the US. I know, for instance, that all regions are not showing warming/cooling at exactly the same rate within the US. If you want to come up with a single figure for the United States as a whole, you have to decide on a methodology for combining disparate results. Perhaps his methodology for combining the raw numbers from different regions of the US is totally kosher. Maybe it isn't, I don't know. But I am suspicious when he includes proxied data for one country and non-proxied data for another. Not a definitive knock against the graph but something to consider. The guy may have something here, I don't really know. But this isn't a terribly honest graph, that much I can tell on my own. The nice thing about the GISS is that it is a uniform data collection. On the ground recordings from different states, different countries, different years have the problem of not being uniform collection. This can mask important changes or create the illusion of changes that aren't really there. GISS, on the other hand, is the same equipment collecting data in the same format across the world. It might be true that the data is somehow incorrect but this graph sure doesn't convince me of that. Judah ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-community/message.cfm/messageid:308724 Subscription: http://www.houseoffusion.com/groups/cf-community/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.5
