There is an informative interview of Judith Curry in Discovery Magazine titled
Discover Interview It’s Gettin’ Hot in Here: The Big Battle Over Climate Science [thanks to Bill DiPuccio for alerting us to the section I have highlighted below]
In Judy’s thoughtful interview responses she said
QUESTION: You’ve talked about potential distortions of temperature measurements from natural temperature cycles in the Atlantic and Pacific oceans, and from changes in the way land is used. How does that work?
JUDITH CURRY’S ANSWER: Land use changes the temperature quite a bit in complex ways—everything from cutting down forests or changing agriculture to building up cities and creating air pollution. All of these have big impacts on regional surface temperature, which isn’t always accounted for adequately, in my opinion. The other issue is these big ocean oscillations, like the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation, and particularly, how these influenced temperatures in the latter half of the 20th century. I think there was a big bump at the end of the 20th century, especially starting in the mid-1990s. We got a big bump from going into the warm phase of the Atlantic Multidecadal Oscillation. The Pacific Decadal Oscillation was warm until about 2002. Now we’re in the cool phase. This is probably why we’ve seen a leveling-off [of global average temperatures] in the past five or so years. My point is that at the end of the 1980s and in the ’90s, both of the ocean oscillations were chiming in together to give some extra warmth.
Judy’s reply reinforces that we need a broader perspective on the climate issue, as we emphasized in
Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union.
This includes both the need to include land use/and cover change as a first order human climate forcing and the more significant role of natural atmospheric/ocean circulations in modulating the climate system.