Share this Article

More Sharing ServicesShare| Share on facebookShare on myspaceShare on googleShare on twitter
On the Origin of the Surface Air Temperature Difference between the Hemispheres in Earth's Present-Day Climate

Georg Feulner, Stefan Rahmstorf, Anders Levermann, and Silvia Volkwardt
[...]

Journal of Climate
Vol. 26: 7136-7150 (Volume publication date: September 2013)
DOI: 10.1175/JCLI-D-12-00636.1
Abstract
In today's climate, the annually averaged surface air temperature in the Northern Hemisphere (NH) is 1°–2°C higher than in the Southern Hemisphere (SH). Historically, this interhemispheric temperature difference has been attributed to a number of factors, including seasonal differences in insolation, the larger area of (tropical) land in the NH, the particularities of the Antarctic in terms of albedo and temperature, and northward heat transport by ocean circulation. A detailed investigation of these factors and their contribution to the temperature difference, however, has to the authors' knowledge not been performed so far. Here the origin of the interhemispheric temperature difference is traced using an assessment of climatological data and the observed energy budget of Earth as well as model simulations. It is found that for the preindustrial climate the temperature difference is predominantly due to meridional heat transport in the oceans, with an additional contribution from the albedo differences between the polar regions. The combination of these factors (that are to some extent coupled) governs the evolution of the temperature difference over the past millennium. Since the beginning of industrialization the interhemispheric temperature difference has increased due to melting of sea ice and snow in the NH. Furthermore, the predicted higher rate of warming over land as compared to the oceans contributes to this increase. Simulations for the twenty-first century show that the interhemispheric temperature difference continues to grow for the highest greenhouse gas emission scenarios due to the land–ocean warming contrast and the strong loss of Arctic sea ice, whereas the decrease in overturning strength dominates for the more moderate scenarios.

Keywords: Energy transport; Ocean circulation; Energy budget/balance; Radiation budgets; Temperature




Authorization required to access PDF

If you have a subscription, sign in with your personal account:
Login

Register
If your institution has a subscription, you can pair your device to gain access:
Pair Device
View Full Site
AMS Journals © 2014

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00636.1?journalCode=clim

Kind of reminds me why I gave up trying to pretend that I understand and just accept the consensus.

BatteriesNotIncluded wrote on Feb 12^th, 2014 at 6:37am:



BatteriesNotIncluded wrote on Feb 12^th, 2014 at 6:37am:


Gotta love the models. Those same ones not now used by IPCC. They use an expert panel instead.

As Australian solar fans considered what the new year will bring in respect of solar energy, news arrived from over the seas of a spectacular bet on solar from one of the world’s richest men. I’m talking of Warren Buffett, the man considered one of the wisest investors in the land (he’s not known as the “Wizard of Omaha” for nothing folks) and his $US2.5 billion swoop for SunPower’s Antelope Valley Solar Projects. The projects are expected to begin construction in 2015.

muso wrote on Feb 12^th, 2014 at 5:23pm:



'Calculated from projections as 5−95% model ranges. These ranges are then assessed to be likely ranges after accounting for additional uncertainties or different levels of confidence in models. For projections of global mean surface temperature change in 2046−2065 confidence is medium, because the relative importance of natural internal variability, and uncertainty in non-greenhouse gas forcing and response, are larger than for 2081−2100. The likely ranges for 2046−2065 do not take into account the possible influence of factors that lead to the assessed range for near-term (2016−2035) global mean surface temperature change that is lower than the 5−95% model range, because the influence of these factors on longer term projections has not been quantified due to insufficient scientific understanding. {11.3}

http://www.climate2013.org/images/report/WG1AR5_SPM_FINAL.pdf

However, the discounted near-term figures were omitted from Table SPM.2.