The gold standard of global warming (despite its inadequacies relative to the assessment of trends in the ocean heat content) is the global average surface air temperature anomaly and its annual trend over time. For example, it is claimed that a +2C anomaly must not be exceeded without major climate consequences (e.g. see).
However, what does a +2C anomaly actually mean. To examine this issue, lets separate this temperature (which we will define as the global average surface air temperature anomaly as GASTA. Then
GASTA = SSATA + TMaxA + TMinA
where SSATA = the sea surface air (e.g. 2m) temperature anomaly; TMaxA = the land surface air (e.g. 2m) maximum temperature anomaly; and TMinA = the land surface air (e.g.2m) minimum temperature anomaly.
We can approximate SSATA quite well, in general, from the sea surface temperature anomaly (SSTA).
Current SSTA values can be viewed http://www.osdpd.noaa.gov/ml/ocean/sst/anomaly.html and http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOD_LSTAD_M&d2=AMSRE_SSTAn_M
Daytime actual surface (but not TMaxA but related to this quantity) can be viewed at http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOD_LSTAD_M#
I have reproduced the NASA MODIS analyses below for March 2010 [on their website, analyses are available back to June 2002].