Global temperature highlights: Year to Date

The average global temperatures

USA National Climatic Data Center — July marked the 36th consecutive July and 329th consecutive month with a global temperature above the 20th century average.

Following the dissipation of La Ni??a in April, record to near-record warmth over land during May, June, and July and increasing ocean temperatures nudged 2012 into the top 10 warmest status for the first seven months of the year.

The combined global land and ocean average surface temperature for the January???July period was 0.95 ??F (0.53 ??C) above the 20th century average of 56.9 ??F (13.8 ??C), marking the 10th warmest such period on record. The margin of error is ??0.16 ??F (0.09 ??C).

Year to date temperatures by month, with 2012 compared to the five warmest years on record

The January-July worldwide land surface temperature was 1.58 ??F (0.88 ??C) above the 20th century average, marking the sixth warmest such period on record. The margin of error is ??0.38??F (0.21??C).

The global ocean surface temperature for the year to date was 0.72??F (0.40??C) above average and ranked as the 11th warmest such period on record. This was the warmest monthly departure from normal since August 2010. The margin of error is ??0.07??F (0.04??C).

In the upper atmosphere, satellite data revealed that the January???July temperature in the lower stratosphere was record coldest for the period, according to two separate analyses performed by the University of Alabama-Huntsville and Remote Sensing Systems.

For more details visit: “State of the Climate” web page at NOAA’s NCDC site: www.ncdc.noaa.gov/sotc/global/2012/7.

From CISRO’s 2012 Marine Climate Change in Australia Report Card comes a similar story on Sea Surface Temperatures in the Southern Hemisphere:

Sea surface temperature (SST) surrounding Australia has undergone significant warming since the early 20th century. Average SST for the most recent 20-year period (1992-2011) was 0.68 ??C warmer than the period 1910-1929.

This significant change in regionally-averaged SST is of similar magnitude to the warming of Australian air temperature (+0.74 ??C) and to globally-averaged land and sea temperatures (+0.71 ??C) between the same two periods. Australian region SST for every decade from 1921-1930 through 2001-2010 has been warmer than the preceding decade.

The rate of globally-averaged temperature rise has accelerated since the mid-20th century; similarly, for Australian waters the rate of warming was 0.08 ??C/decade from 1910-2011 and 0.11 ??C/decade from 1950-2011.

Since the first Report Card in 2009, the then warmest year (1998) for Australian region SST has been superseded by that in 2010. 15 of the 20 warmest years within the 102-year instrumental record have all occurred within the last 20 years.

More online at: Lough J. et al (2012) Temperature. In A Marine Climate Change Impacts and Adaptation Report Card for Australia 2012 (Eds. E.S. Poloczanska, A.J. Hobday and A.J. Richardson).

CSIRO Marine and Atmospheric Research
Ecosciences Precinct
GPO Box 2583
Brisbane, QLD 4001

Tel: (07) 3833-5956
Website:?? www.cmar.csiro.au/climateimpacts/