Global Temperature Increases

Regional Deviation Charts

The deviation charts are no longer updating,
but for the year from July 1, 2012 to July 1, 2013 show
• two-week deviations averaged over global regions
• long-term deviations from normal, as indicated by 3-month averages
(that is, the two weeks or three months preceding any point on the chart).

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  The regional deviation charts are based on recent hourly temperature observations and long-term normal temperatures at 172 airport weather stations in 56 countries worldwide.  Here is an example showing global deviations from long-term normal temperatures.  To see more click
  The global deviations have a minimum 3-month average of 0.53 degrees Fahrenheit = 0.29 degrees Celsius during February 19 to May 20, and a maximum 3-month average of 1.63 degrees Fahrenheit = 0.91 degrees Celsius during June 16 to September 14.

The hourly temperature deviation from normal for each station in a region is averaged for the previous two weeks.  These are then averaged over all stations in a region.  The global deviation is an average of all 172 stations without regard to region.

For each region, the last two weeks' magenta "observed" curve corresponds to
14 days x 24 temperatures per day = 336 temperatures.

The typical period of record is about 67 years of daily lows and highs, and the normal curve depends on the mean low and mean high of this record for each day.  Thus, each airport's green "normal" curve corresponds to
14 days x 2 temperatures per day per year x 67 years = 1,876 temperatures.

The global 2-week deviation, which is based on an average of 172 airports, thus depends on about
172 x 336 = 57,800 temperatures observed over the past two weeks, and about
172 x 1,876 = 322,700 historical temperatures, for a total of about
380,500 temperatures.

For each region, the green curve averages the last 3 months, or 91 days, of the 2-week deviations.  The oldest of the 91 days depends on temperatures for 14 days.  The 3-month deviation therefore depends on temperatures for (91 - 1) + 14 = 104 days.  Consequently, the 3-month global deviation depends on about
(91 - 1 + 14) days / 14 days x 57,800 = 429,000 temperatures in the last 15 weeks, and
(91 - 1 + 14) days / 14 days x 322,700 = 2,397,000 historical temperatures, for a total of about
2.8 million temperatures.

The regional temperature deviation graphs demonstrate how the region's temperature is deviating from the long-term normal, as averaged over the representative airports for the region.  The global deviation is the mean for all 172 airports worldwide.

For global deviations listed by world region, click the following link:

For a map of global deviations by world region, click the following link:

For a discussion of how long fossil fuel will last and what that implies about ultimate global warming, click the following link: