Each month, the National Climatic Data Center (NCDC, a branch of NOAA) issues a temperature report for the previous month’s worldwide land and sea temperatures and precipitation.
As far as the temperature goes, the September temperatures can simply be described as more of the same.
Just as August’s combined land and sea temperature was the warmest on record for that month, so is September’s.
And in both cases, the oceans led the way — warmest ever, while land temperatures were only close to a record.
September Temperature By The Numbers
The combined global land and sea temperature for September was 1.30 degrees (Fahrenheit) warmer than the 20th century average; it was the warmest September since record-keeping began in 1880. This was the fourth month in the last five to set a new monthly record for combined land and sea temperature.
The oceans averaged 1.19 degrees above the 20th century average. This was not only a record for September; it was the greatest departure from the long-term average for any month in the 135 years of record keeping. It broke the previous record of 1.17 degrees above average, which was held by …. (Can you guess?) …. the previous month, August.
As has been the case for several months recently, land surface temperatures did not set a worldwide record. September, 2014 was only the sixth warmest in the 135 years of records. But there were some notable hotspots.
- Western Australia set an all-time September temperature record, nearly five degrees (4.95) above the average of data that have been compiled since 1900.
- Every German state reported above normal temperatures.
- At least one reporting station on every continent set a record for September warmth.
January Though September, 2014 And Past Full Year Combined Land And Sea Temperature
January to September, 2014 global temperature is now tied with 1998 as the warmest such period on record.
With four of the last five months’ overall temperature exceeding the previous high for the month, there is a very good prospect that 2014 will set a new calendar year record for combined land and ocean warmth.
The global air and sea temperature for the past 12 months — October, 2013 through September, 2014 — is the warmest 12 month period on record at 1.24 degrees above the 20th century average.
September, 2014 Precipitation
Precipitation amounts can vary widely even from one minute to the next, let alone from month to month. However, there were some significant precipitation numbers in September.
- The United Kingdom reported the driest September in its 105 years of data, with just 20% of average precipitation. This is especially noteworthy because the period January through August was the wettest such period on record. Increased variability of temperature and precipitation is a widely forecast result of global warming.
- Northern Ireland got only 7% of normal rainfall.
- The monsoon on the Indian sub-continent dropped only 88% of normal precipitation. However, despite a weak start, the monsoon had a strong finish, bringing over a foot of rain to parts of northwest India and Pakistan in early September. The rain triggered mudslides that killed more than 400.
What Can We Conclude From The Temperature Trend?
It may be somewhat comforting to climate-change deniers to note that the global land temperatures are not quite reaching monthly all-time highs. However, with the ocean surface temperatures increasing at an accelerating pace, the news about an overheating earth may be even worse than it appears.
Some of the increased heat associated with global warming may be hidden in the deeper parts of the ocean. If that is the case, the heat will sooner or later be transferred to the atmosphere, and the already scary predictions for future temperatures may have to be adjusted upwards.
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