Below are maps of the mean surface temperature anomaly for the past month, the past three months, and the past 12 months. Regional weather patterns, apparent on the monthly time scale, tend to disappear in averages over longer time scales. In the chart in the lower right we show the 12-month running means of the global land-ocean temperature anomalies.
Most recent one, three and 12 month mean global temperature anomaly maps, and 12-month-running mean global temperature anomaly. (Also in PDF, last modified 2016/01/20, now with GHCN version 3.3.0 and ERSST v4).
The figure below shows 60-month (5-year) and 132-month (11-year to minimize the effect of the solar cycle) running means of the surface temperature deviation from the 1951-1980 mean. This graph makes clear that global warming is continuing it did not stop in 1998. The year 1998 was remarkably warm relative to the underlying trend line in association with the "El Nino of the century".
(a) Annual and 5-year mean global surface temperature anomalies. The last data (open square) is the Jan-Nov 2015 mean. (b) 60-month and 132-month running means. The base period is 1951-1980 for both (a) and (b). (Also in PDF, Data through December 2015 are used for computing the means. last modified 2016/01/20, now with GHCN version 3.3.0 and ERSST v4.)
Note 1: GHCN-M version 3 replaced version 2 in GISS temperature analysis because NOAA/NCDC no longer updates version 2. (since 2011/12/15)
GHCN v3.2.2 was replaced by v3.3.0 (since 2015/06/13, See NASA GISS Updates to Analysis page for details.)