Progression of Recent Warming Trends Across the Continents and Oceans

Abstract:

As part of the PAGES (Past Global Changes) Ocean2k project^1-2 we examine the features of recent sea surface temperature trends in ocean regions where palaeoclimate data allow for moderate to high-resolution reconstructions that extend back over several centuries. Centennial-scale resolution marine observations independently suggest that the global ocean cooling trend observed from 0-1800 CE was reversed in the last two centuries. Building on the results of earlier continental-scale temperature reconstructions from the PAGES 2k community³, we compare the initiation point for recent significant warming between various land and ocean regions. Preliminary results suggest recent significant warming in the tropical oceans was near synchronous with warming of the Northern Hemisphere land masses, in contrast with a potential poleward lag in warming of the Southern Hemisphere land masses. Multi-model climate simulations are used to assess where there is high fidelity between recent warming trends determined by palaeoclimate observations and simulations, and to examine regions of data-model divergence.

References:

1. Tierney, J.E., Abram, N.J., Anchukaitis, K.J., Evans, M.N., Giry, C., Kilbourne, K.H., Saenger, C.P., Wu, H.C., Zinke, J. (in prep). Tropical sea-surface temperatures for the past 400 years reconstructed from coral archives.

2. PAGES Ocean2k LR Group (in prep.) Robust global ocean cooling trend for the pre-industrial Common Era.

3. PAGES 2k Consortium (2013). Continental-scale temperature variability during the last two millennia. doi: 10.1038/NGEO1797

Website:

http://www.pages-igbp.org/workinggroups/ocean2k