After the hottest decade on record, it’s the hottest year on record, hottest week of all time in satellite record* and we may be at record low Arctic sea ice volume

But how about the world’s heaviest hailstone?

FoxNews had me on twice for the big snowstorms (during the hottest winter on record), but no invitations during the record-smashing heat waves hitting the nation and world. Go figure!

This is Roy Spencer’s much rejiggered UAH satellite data comparing 2010 lower trososphere temperatures (green) with average temps (blue) and record highs since 1979 (purple):

*It would appear we’ve set the all-time record high absolute temperature in the satellite dataset for the last week or two, but see John Christy caveat below.

NOAA’s annual State of the Climate Report for 2009 (video here) reports that “Past Decade Warmest on Record According to Scientists in 48 Countries”:

Each of the last three decades has been much warmer than the decade before. At the time, the 1980s was the hottest decade on record. In the 1990s, every year was warmer than the average of the previous decade. The 2000s were warmer still.”The temperature increase of one degree Fahrenheit over the past 50 years may seem small, but it has already altered our planet,” said Deke Arndt, co-editor of the report and chief of the Climate Monitoring Branch of NOAA’s National Climatic Data Center. “Glaciers and sea ice are melting, heavy rainfall is intensifying and heat waves are more common. And, as the new report tells us, there is now evidence that over 90 percent of warming over the past 50 years has gone into our ocean.”

And the 2010s will be the hottest decade on record and then the 2020s will be the hottest decade on record. The only question is whether humanity is going to continue to staying on this self-destructive emissions path so that every decade this century will be the hottest on record, with an ultimate temperature increase by 2100 of perhaps 9°F or more:

McClatchy reports something that CP readers have known for a while:

Global warming: NASA says it’s the hottest year on record

Scientists at the NASA Goddard Institute for Space Studies reported recently that the average global temperature was higher over the past 12 months than during any other 12-month period in history. The National Oceanic and Atmospheric Administration has released corroborating data, adding that the past four months, including June, have each individually been the hottest on record as well….

The average global temperature, computed over a 12-month period, reached a new record in May and held steady for the month of June, he said. This was despite the recent minimum in solar activity, which should have had a cooling effect on Earth.Apparently, Ruedy said, the solar cycle “has much less impact than the warming trend.”

A La Ni±a seems all but certain as central tropical Pacific ocean temperatures have been dropping steadily, which is perhaps what makes the satellite data at top so surprising, since it tends to be the most sensitive to the El Ni±o Southern oscillation.

You can do your own graphing of the UAH data (click here). The BlackBoard reports that Roy Spencer says:

The record highs and lows are based upon the entire MSU MT record back to 1979. To do this, we intercompared our official UAH TMT product, including the average annual cycle added to the anomalies, with just the Aqua averages over the Aqua period of record since mid-2002. This provided an intercalibration between Aqua-only and UAH official. This then allowed us to go back through and use all of the UAH TMT data to find record highs and lows back through 1979.

This is something I and others have requested for a while, so I take it that the plot at the top does in fact show the lower troposphere experienced the hottest week in the satellite record — though there are presumably recalibrations before the final reporting, since, for instance, March 2010 was easily the hottest March in the satellite record (UAH and RSS), but the top plot doesn’t indicate that.

UPDATE: John Christy emails me with the following caveat on the UAH temperatures for July from that website:

Please be aware that the values displayed have not been completely calibrated for the entire period (this has to do with some matching between the two different channel weighting functions through the annual cycle that is done in our normal processing at the end of the month but which is not done on the day-to-day chart you show.) Improving the daily chart is work that is on-going.

And while everyone’s eyes are on the Arctic sea ice extent data, which right now appears not to be matching 2007’s record-setting pace, the Polar Science Center’s PIOMAS model puts the far more important metric of Arctic ice volume at a record-smashing low:

Daily Sea Ice volume anomalies for each day are computed relative to the 1979 to 2009 average for that day. The trend for the 1979- present period is shown in blue. Shaded areas show one and two standard deviations from the trend.

Note that PSC says, “September Ice Volume was lowest in 2009 at 5,800 km^3 or 67% below its 1979 maximum.” If I’m reading the two graphs right, then we are pretty close to the all-time volume record right now.


If you want to know why PIOMAS is a credible model , you can read the post by the National Snow and Ice Data Center’s Walt Meier on this at WattsUpWithCrap — yes, he really posted there:

PIOMAS has been specifically validated for ice thickness using submarine and satellite data ( Of course, the PIOMAS model estimates are not perfect, but they appear to capture the main features of the ice cover in response to forcings over seasonal and interannual scales….

PIOMAS includes much more up-to-date model components (developed during the late 1990s early 2000s) with significant improvements in how well the model is able to simulate the growth, melt, and motion of the ice cover. In particular, the model do a much better job at realistically moving the ice around the basin and redistributing the thickness (i.e., rafting, ridging) in response to wind forcing. Thus, the thickness fields are likely to be more realistic than PIPS. The primary references for PIOMAS are: Zhang and Rothrock (2003), Zhang and Rothrock (2001), Winton (2000), Zhang and Hibler (1997), Dukowicz and Smith (1994).

… for the reasons stated above, I would trust the PIOMAS model results more for seasonal and interannual changes in the ice cover. I very much doubt that anyone familiar with the model details would unequivocally trust PIPS over PIOMAS.

But what about the PIOMAS volume anomaly estimates? How can they be showing a record low volume anomaly when there is less of the thinner first-year ice than in previous years as seen in ice age data? Doesn’t this mean that PIOMAS results are way off? Well, first, it is quite possible that the model may currently be underestimating ice thickness. No model is perfect. However, there is a possible explanation for the low volume and the PIOMAS model may largely be correct.

The areas that in recent years have been first-year ice that are now covered by 2nd and 3rd year ice will increase the volume — in those regions. However, compared to the last two years, there is even less of the oldest ice (see images below — I also included 1985 as an example of 1980s ice conditions for comparison). The loss of the oldest, thickest ice may more than offset the gain in volume from the 2nd and 3rd year ice. Also, it’s been a relatively warm winter in the Arctic, so first-year ice is likely a bit thinner than in recent years. Finally, the extent has been less than the last two years for the past couple of months. So the PIOMAS estimate that we are at record low volume anomaly is not implausible.

Early May ice age for: 1985 (top-left), 2008 (top-right), 2009 (bottom-left), and 2010 (bottom-right). OW = open water (no ice); 1 = ice that is 0–1 year old (first-year ice), 2 = ice that is 1–2 years old (2nd year ice), etc. Images courtesy of C. Fowler and J. Maslanik, University of Colorado, Boulder. Updated from Maslanik et al., 2007.

Regardless of what happens this summer though, the most important fact is that, despite some areas of the Arctic being a bit thicker this year, the long-term thinning and declining summer ice extent trend continues.

In his subsequent post, Dr. Meier debunks more of their nonsense and concludes:

There is little doubt in the sea ice community that during summer the Arctic can become ice-free and will become ice-free as temperatures continue to rise.

Duh. I suppose that will only come as a shock to Watts, Goddard, and their fellow Kool-Aid drinkers.

Finally, I’m pretty sure there’s nothing on this in the scientific literature — and I have great confidence that the disinformers will assert it must be evidence against the theory of human-caused global warming — but Accuweather reports:

Hail and High Water? Sorry, couldn’t resist!