An alternative explanation for differential temperature trends 3 at the surface and in the lower

7 [1] This paper investigates surface and satellite temperature trends over the period 8 from 1979 to 2008. Surface temperature data sets from the National Climate Data 9 Center and the Hadley Center show larger trends over the 30-year period than the 10 lower-tropospheric data from the University of Alabama in Huntsville and Remote 11 Sensing Systems data sets. The differences between trends observed in the surface and 12 lower-tropospheric satellite data sets are statistically significant in most comparisons, 13 with much greater differences over land areas than over ocean areas. These findings 14 strongly suggest that there remain important inconsistencies between surface and satellite 15 records.