A New Mode of Decadal Variability in the Pacific Ventilated Thermocline and its Influence on Global Warming

Add to your list(s) Download to your calendar using vCal

• Daniel P. Schrag, Harvard University
• Monday 23 April 2018, 11:00-12:00
• Harker Seminar Room, Department of Earth Sciences.

If you have a question about this talk, please contact Alexandra Turchyn.

Argo data reveal the development of a thickness anomaly in the lower levels of the ventilated thermocline of the South Pacific starting in 2010. Data through 2016 show this anomaly propagating westward and towards the equator. Theory suggests that this anomaly will reduce the velocity of the equatorial undercurrent (EUC) when it approaches the equator; this is supported by climate model results with enhanced vertical resolution in the thermocline, which also show a strong influence on eastern Pacific sea surface temperatures. We propose that the propagation of such anomalies in the structure of the ventilated thermocline from the southeastern Pacific to the western equatorial Pacific may explain some of the decadal variability observed in the equatorial Pacific that also affects global temperature. This mechanism improves our understanding of variability in the global temperature record, implying that the stepwise warming pattern over the 20th century is primarily due to internal variability in the ocean rather than aerosol forcing. It also provides guidance for climate model development that may enable simulations to better capture internal variability andimprove climate forecasts.

This talk is part of the Cambridge Centre for Climate Science series.

This talk is included in these lists:

• Cambridge Centre for Climate Science
• Cambridge Energy Seminars
• Climate Science Seminars within Cambridge
• Harker Seminar Room, Department of Earth Sciences
• NanoDTC Energy Materials Talks
• Talks related to atmosphere and ocean dynamics and climate science
• history
• seminars

Note that ex-directory lists are not shown.