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Record Global Warm Streak Extended Through June

By Alyson Kenward

Last week, while others here at Climate Central were blogging about the East Coast heat wave, I was enjoying some of the cooler weather that much of the West has experienced this spring and summer. But since arriving back in New Jersey, I can’t help but think that it is much hotter than usual around here. And according to an announcement yesterday from the National Oceanic and Atmospheric Administration (NOAA), there’s some truth to that — it actually has been warmer than average. Much warmer. In fact, last month was the warmest June on record globally and the eighth warmest in the U.S., according to records that date back more than 130 years.

In their monthly report of national climate data, NOAA reported that the June average land surface temperature in the US was more than two degrees Fahrenheit warmer than the long-term average. For the states of New Jersey, Delaware and North Carolina, it was the hottest June on record, and only Oregon and Washington saw cooler than average temperatures. It wasn’t just the eastern seaboard that felt the heat; parts of South America, Europe and most of China were subject to record-breaking heat waves.

So what of that cool weather the west coasters have been complaining about? I’ve heard nothing but whining about the cold and the rain this spring and summer from friends and family on the other side of the country. Well, one look at the global map of June’s temperature anomalies shows you that while, yes, parts of the American West, Alaska, and some of portions of the Pacific Ocean were cooler than average, nearly everywhere else on the planet experienced warmer than average conditions. 

Temperature Anomalies
This map shows average surface temperature anomalies (departures from normal) for the month of June 2010. Click image to see larger version. Credit: NOAA/NCDC

NOAA reports temperature anomalies, or the difference in temperature from the average value, rather than the absolute temperature in order to get a more accurate representation of temperature changes. Whereas the exact location of a weather monitoring station can affect the reading for average temperature, the relative changes in temperature tend to be consistent no matter where in a region the measurement is taken.

Across the entire globe, the land surface temperature was nearly two degrees Fahrenheit warmer than the 20th century average, breaking the previous record by 0.2 F.  The combined global land and ocean average surface temperature for June was the warmest on record at 61.1 F, which is 1.22 F above the 20th century average of 59.9°F, according to NOAA. This was the fourth consecutive month that was the warmest on record, NOAA stated.

Though this made it the warmest June on record, the global warmer-than-average trend actually spans further back than last month. The NOAA report shows that the global combined land and ocean surface temperature of 57.5 F was the warmest January-June period on record, at 1.22 F above the 20th century average.

Part of the reason that this year has been so warm thus far has been due to the warming influence of El Nino, which is an atmosphere and ocean cycle in the Pacific. However, El Nino is no longer present, and a La Nina event featuring colder-than — average water in the equatorial Pacific is now developing. This could prevent 2010 from setting a new annual temperature record.

But wait, there’s more. According to NOAA’s State of the Climate report for the month of June, it was actually “the 304th consecutive month with a global temperature above the 20th century average.” That means that the last month when the global average temperature was below that average was February 1985!

NOAA isn’t the only group tracking global temperature and other organizations like NASA are finding the same trends.

Mean Surface Temperature Anomaly
These maps show global average land and ocean surface temperature anomalies (departures from average). The map above includes the most recent one-, three- and 12-month mean global temperature anomaly maps, and 12-month-running mean global temperature anomaly. Click on the map above for a larger version.

So, all signs are pointing to the fact that yes, it is hot outside — hotter than normal. Although, with a trend going on 305 months, it looks like we might have to start thinking about a new normal.


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