I use the Lengthened Rebuilt Ocean Body Temperatures (ERSST) investigation of Reynolds and Smith (1994), variation 3b (Smith et al

2008), which takes vessel and you can buoy measurements and you will provides a beneficial gridded dataset during the 2° quality having fun with an optimum interpolation approach. We use the climatological research determined ranging from 1981 and you can 2010. Once the a great metric into the interhemispheric change regarding exotic SST, i assess ?SST since the spatially weighted SST between your equator and you can 20°Letter without any spatially adjusted SST involving the equator and 20°S. step one

(iii) Atmospheric heat transportation across the equator

Brand new atmospheric temperatures transportation is derived from this new Federal Centers having Environmental Forecast (NCEP) four-times-every single day reanalysis industries (Kalnay mais aussi al. 1996) with a beneficial (horizontal) spectral resolution from T62 and you will 17 straight accounts. The fresh atmospheric temperatures transportation try computed from married women looking for men the earliest controlling the new atmospheric bulk funds throughout the reanalysis study having a beneficial barotropic piece of cake correction like in Trenberth (1997) and you can then calculating the new meridional flux out of moist fixed opportunity dos and you may vertically integrating. This method can be used so you can write monthly averaged atmospheric temperature transportation away from 1981 so you’re able to 2010 plus the climatological mediocre more this period can be used inside studies.

We use longwave and shortwave radiative fluxes from the Clouds and Earth’s Radiant Energy System (CERES) experiment (Wielicki et al. 1996) to calculate ?SWABS? and ?OLR?. All calculations are performed separately for each of the four CERES instruments (FM1 and FM2 on Terra from 2000 to 2005 and FM3 and FM4 on Aqua from 2002 to 2005). We then average the results over the four instruments. The quantity ?STOR_atmos? is calculated as the finite difference of the vertically integrated temperature and specific humidity from the NCEP reanalysis climatology. As in Donohoe and Battisti (2013), ?SHF? is calculated as the residual of radiative heating, atmospheric storage, and the atmospheric heat transport divergence (from NCEP reanalysis).

The seasonal amplitude and stage utilized in our investigation is actually defined because amplitude and you will stage of one’s yearly harmonic.

2) Results

A scatterplot of the monthly average P_Penny versus AHT_EQ and ?SST is shown in Fig. 3. The precipitation centroid varies from 5.3°S in February to 7.2°N in August and has an annual average of 1.65°N. This seasonal cycle of ITCZ location is slightly damped (equatorward) of other common metrics of ITCZ location (e.g., the latitude of maximum zonal mean precipitation, Xian and Miller 2008). It can be seen that P_Cent spends four months of the year in the Southern Hemisphere during the austral summer as the most intense precipitation is found in the South Pacific convergence zone at this time of year (not shown) and the zonal mean precipitation maximum moves to southern latitudes. We note that although the marine ITCZ defined in the eastern Pacific and Atlantic by Waliser and Gautier (1993) never moves south of the equator, the global ITCZ defined in the same study does move into the Southern Hemisphere and agrees very well with our precipitation centroid.

(top) Scatterplot of your regular course away from exotic precipitation centroid against mix-equatorial atmospheric temperature transportation. Per mix try considering the fresh monthly mediocre additionally the size of the cross on each axis is short for the fresh 95% depend on period reviewed on interannual variability. The occupied field is the yearly average. The newest dashed line is the linear greatest match to the monthly averages. (bottom) Once the at the most readily useful, however for the fresh new warm rain centroid against the brand new interhemispheric difference in tropical SST.

(top) Scatterplot of your own regular course out-of exotic rain centroid vs mix-equatorial atmospheric heat transportation. Each cross is predicated on the brand new month-to-month mediocre plus the duration of get across on every axis is short for the new 95% trust interval reviewed regarding the interannual variability. The new filled field is the annual average. The dashed range is the linear better fit into the month-to-month averages. (bottom) Since from the best, but for brand new warm rain centroid compared to the new interhemispheric difference between exotic SST.