May Temperatures (preliminary)
Global composite temp.: +0.18 C (+0.32 °F) above seasonal average
Northern Hemisphere.: +0.40 C (+0.72 °F) above seasonal average
Southern Hemisphere.: -0.05 C (-0.09 °F) below seasonal average
Tropics.: +0.03 C (+0.05 °F) above seasonal average
April Temperatures (revised)
Global composite temp.: +0.21 C (+0.38 °F) above seasonal average
Northern Hemisphere.: +0.31 C (+0.56 °F) above seasonal average
Southern Hemisphere.: +0.10 C +0.18 °F) above seasonal average
Tropics.: -0.13 C (-0.23 °F) below seasonal average
Notes on data released June 1, 2018
The global temperature anomaly for May 2018 changed only slightly from April, with the Southern Hemisphere dropping to its coolest measurement in five years. However, we do see some regional hints of changes to come. The tropical tropospheric temperature moved slightly into positive territory indicating, as NOAA has announced (http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolutionstatus-fcsts-web.pdf), that the cool tropical Pacific condition known as La Niña is over and that we may see-saw back to the warm pattern of El Niño this coming winter. Stay tuned.
The largest local departures from average were not exceedingly far from each other; the coldest near Greenland’s capital Nuuk at -4.1 C (-7.3 °F) and the warmest near Ostersund Sweden at +4.9 C (+8.8 °F). Very clearly seen in the map of May’s temperatures is the extremely warm area over the conterminous U.S. averaging +1.93 C (+3.47 °F) above the 1981-2010 average. This is the highest U.S. value in the 40 months of May we have now observed from space since late 1978.
As part of an ongoing joint project between UAH, NOAA and NASA, Christy and Dr. Roy Spencer, an ESSC principal scientist, use data gathered by advanced microwave sounding units on NOAA and NASA satellites to get accurate temperature readings for almost all regions of the Earth. This includes remote desert, ocean and rain forest areas where reliable climate data are not otherwise available.
The satellite-based instruments measure the temperature of the atmosphere from the surface up to an altitude of about eight kilometers above sea level. Once the monthly temperature data are collected and processed, they are placed in a "public" computer file for immediate access by atmospheric scientists in the U.S. and abroad.
The complete version 6 lower troposphere dataset is available at http://www.nsstc.uah.edu/data/msu/v6.0/tlt/uahncdc_lt_6.0.txt
Archived color maps of local temperature anomalies are available at http://nsstc.uah.edu/climate/
Neither Christy nor Spencer receives any research support or funding from oil, coal or industrial companies or organizations, or from any private or special interest groups. All of their climate research funding comes from federal and state grants or contracts.