Sunday, 1 January 2012

Rohde et al. 2011ish - Berkeley Earth Temperature Averaging Process

Rohde et al. (2011) The paper describes a process for estimating the temperature at any point on the Earth’s land surface using a discontinuous network of stations of any geographical distribution. The method was applied to the GHCN network and an estimate of the global average temperature was calculated back to 1800. Uncertainties in the global average were also calculated that account for spatial sampling and data errors.
The paper is important in two ways. Firstly from a scientific perspective it is important because it takes a new and statistically innovative look at the problem of estimating global land temperatures. That it confirms global average land surface air temperature trends is unsurprising, its greatest scientific impact will be in helping to elucidate trends and variability at smaller scales where uncertainties are much larger. The length of the record is 50 years longer than the longest current estimate produced by CRU and the proposed uncertainty range is narrower than those estimated for other data sets. Secondly it has a role to play in the wider discussion of climate change about which I will say nothing other than to acknowledge it.

Foster and Rahmstorf 2011 - The True Global Warming Signal

Everyone knows that the temporary flickers in the global temperature curve are the marks of El Ninos, La Ninas and volcanic explosions. The slower variations are the symptoms of changes in the overall forcing due to the vagaries of solar output, accumulations of greenhouse gases in the atmosphere and others, or they arise as natural variations internal to the climate system.