CSIRO&MK3.6.0 SOUTHERN HEMISPHERE HEAT AND MOMENTUM CHANGE UNDER UNIQUELY FORCED ATTRIBUTION AND DETECTION EXPERIMENTS Mark Collier 1 , Kwang1Yul Kim 2 , Tony Hirst 1 , Leon Rotstayn 1 and Stephen Jeffrey 3 1. CSIRO Marine and Atmospheric Research, Victoria, Australia 2. School of Earth and Environmental Sciences, Seoul, South Korea 3. Queensland Centre for Climate Change Excellence, Queensland, Australia
10
Embed
CSIRO&MK3.6.0-SOUTHERN- HEMISPHERE-HEAT … · CHANGE-UNDER-UNIQUELY-FORCED-ATTRIBUTION-AND-DETECTION-EXPERIMENTS! ... 31-LEVEL-T63 YX2-OCEAN-DYNAMIC ... • Mk36 trend in the SH
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
CONCLUSIONS-!!• Anthropogenic Aerosols (AAs) in coupled climate models are required to capture 20th
century changes in near surface global air temperature.
• Mk3A/Mk36 hemispheric time-series of net heat flux and heat content have similar features, however there are some noticeable differences.
• Mk36 has a stronger Northward heat flux trend for the Atlantic than Mk3A, and a mostly Northward heat flux trend for the Global value. The Indo-Pacific value is highly variable on annual and decadal time-scales. The Atlantic is a particularly efficient at moving heat Northwards at all latitudes and on all time-scales over the 20th century.
• Mk36 trend in the SH net heat flux in the last few decades of the 20th century, and a contrasting Indo-Pacific overturning circulation hint at uniquely different regionally based aerosol-induced air-sea interaction: combination of model improvements and an improved aerosol emissions database.
• AAs result in greater heat loss in the North Atlantic than the Indo-Pacific system introducing a range of “aerosol-induced” circulation changes regionally linked to the Ocean Conveyor. We have found a 17 (5) [-2]% change in NADW (ITF) [DPT] when we compare the last 1980-2005 years of aerosol-induced experiments to the same length period directly after PI times.
• Changes to the surface ocean currents & Conveyor in the Mk36 model have a much “richer” structure than compared to Mk3A. The strengthening of the Atlantic heat transport mitigates the slow-down of the Atlantic overturning due to GHGs. Into the future this protection of the Conveyor by AAs is likely to weaken.