2013 Was 4th Warmest Year on Record, or 7th Warmest

The National Oceanic and Atmospheric
Administration has just released it global temperature calculations
and has concluded that 2013 is the fourth
hottest year on record since 1880. From NOAA:

The year 2013 tied with 2003 as the
fourth warmest year globally since records began in 1880. The
annually-averaged temperature across global land and ocean surfaces
was
0.62°C (1.12°F) above the 20^th century average and
marks the 37^th consecutive year (since 1976) that the
annual temperature was above the long-term average. Currently, the
warmest year on record is 2010, which was 0.66°C (1.19°F) above
average. To date, including 2013, 9 of the 10 warmest years on
record have occured during the 21^st century. Only one
year during the 20^th century—1998—was warmer than 2013.
The global annual temperature has increased at an average rate of

0.06°C (0.11°F) per decade since 1880 and at an average rate of

0.16°C (0.28°F) per decade since 1970.

NASA calculates global average temperature differently. As the
Associated Press
reported NASA…

…ranked last year as the seventh warmest on record, with an
average temperature of 58.3 degrees (14.6 Celsius). The difference
is related to how the two agencies calculate temperatures in the
Arctic and other remote places and is based on differences that are
in the hundredths of a degree, scientists said.

Both agencies said nine of the 10th warmest years on record have
happened in the 21st century. The hottest year was 2010, according
to NOAA.

According to the satellite temperature data from University of
Alabama in Huntsville climatologists John Christy and Roy Spencer,

2013 was the fourth warmest year since that data began being
collected in 1979.

NOAA notes that the global average temperatures increased at
rate of 0.16 degrees C per decade from 1970 until 2013. However,
its
own data shows that the per decade rate of increase since 1998
until now is 0.04 degrees C, i.e., one-fourth the rate since 1970
and about one-fifth the 0.21 degrees C per decade average rate
predicted by computer climate models.

What is causing this recent “hiatus” in warming is hotly
contested. On the one hand, some argue that the “missing”
heat is hiding in the deep ocean, and on the other hand, some
assert the computer
climate models’ climate sensitivity to extra atmospheric carbon
dioxide is way too high. More data needed.