Examining the Relationship Between Precipitation and TOA Net Radiation

1. Examining the Relationship Between Precipitation and TOA Net Radiation Kim Chamales MPO 524 Final Project Thursday, May 2nd, 2013

2. My Research • Examining the effects of external forcing on precipitation in the tropical Atlantic • Looking at the relationship between precipitationand TOA net radiation in two simulations with varying precessional forcing • Examining changes in tropical Atlantic precipitation – so changes in monsoons and ITCZ

3. My Data • GFDL-CM2.1 (fully coupled) • Two simulations representing both extremes of precessional forcing • Climatological monthly averages from 20 years of the equilibrium climate • Over entire globe: 144x90x12

4. Precessional Forcing 1. Winter Solstice (WSOL): NH wintersolstice closest to the sun 2. Summer Solstice (SSOL): NH summersolstice closest to the sun JJA DJF DJF JJA

5. Precipitation Difference: WSOL – SSOL Earth is closer to the sun Earth is farther from the sun

6. Why use this analysis? • Can’t think of monsoons as land and sea breezes being driven by surface temperature change in TOA net radiation surface energy storage atmos energy flux div ocean energy flux div Land and atmospheric energy storage are very small so they are neglected. • Merlis et al. (2012b), Equations 5 & 6

11. 200 300 0 100

12. Summary • Examining spatial and temporal relationship between precipitation and TOA net radiation • Although it gives some useful information about the relationship, the variability between the two in the tropics is very large

13. Thank You!

14. Extra Slides

20. The downfall of using climatological averages… • Can’t do a lot of the analyses we learned in class because we don’t have a time series! • However, the relationships that exist in the data should still exist – we have just averaged out a lot of the variability • Can still use certain analyses to gather useful information