US sets record temperatures

And now the weather from Europe...

Climate in northern Europe reconstructed for the past 2,000 years: Cooling trend calculated precisely for the first time
Calculations prepared by Mainz scientists will also influence the way current climate change is perceived / Publication of results in Nature Climate Change

An international team including scientists from Johannes Gutenberg University Mainz (JGU) has published a reconstruction of the climate in northern Europe over the last 2,000 years based on the information provided by tree-rings. Professor Dr. Jan Esper's group at the Institute of Geography at JGU used tree-ring density measurements from sub-fossil pine trees originating from Finnish Lapland to produce a reconstruction reaching back to 138 BC. In so doing, the researchers have been able for the first time to precisely demonstrate that the long-term trend over the past two millennia has been towards climatic cooling. "We found that previous estimates of historical temperatures during the Roman era and the Middle Ages were too low," says Esper. "Such findings are also significant with regard to climate policy, as they will influence the way today's climate changes are seen in context of historical warm periods."

The new study has been published in the journal Nature Climate Change. Was the climate during Roman and Medieval times warmer than today? And why are these earlier warm periods important when assessing the global climate changes we are experiencing today? The discipline of paleoclimatology attempts to answer such questions. Scientists analyze indirect evidence of climate variability, such as ice cores and ocean sediments, and so reconstruct the climate of the past. The annual growth rings in trees are the most important witnesses over the past 1,000 to 2,000 years as they indicate how warm and cool past climate conditions were.

"This figure we calculated may not seem particularly significant," says Esper. "However, it is also not negligible when compared to global warming, which up to now has been less than 1°C. Our results suggest that the large-scale climate reconstruction shown by the Intergovernmental Panel on Climate Change (IPCC) likely underestimate this long-term cooling trend over the past few millennia."

http://www.uni-mainz.de/eng/15491.php

Stay tuned.

Maybe SC can explain how tree rings are used to determine cooling/heating. I always thought they could only tell you how much rain was received each year.

Raees wrote: Maybe SC can explain how tree rings are used to determine cooling/heating. I always thought they could only tell you how much rain was received each year.

Good question, there could be a bunch of different reasons why tree rings are thick one year and thin the next year.

Droughts, heat, cold, extra nutrients in the soil, etc.

Raees wrote: Thank you. Multiply that heat sink effect by 10's of thousands of growing cities adding more concrete all the time and what do you think happens?

It doesn't get as cool at night in the city as it otherwise would if the city were either not there at all or if it were a smaller city. What happens in an immediate area is not indicative of climate, it is indicative of the weather in that immediate area. Last year Colorado had the 35th (IIRC) wettest spring on record, this year it has had one of the, if not the, driest on record. Up in Montana, June finished out as only the 5th time in the past 13 years when precipitation was below normal.

Have we forgotten about the 2010-2011 snowfall already? Let me remind you since it appears to have slipped your mind.

For the water year to-date (which begins Oct. 1), Bly has measured 168.1 inches of snow, about 26 percent above average. The snow-water equivalent for the year-to-date is 13.93 inches, a solid 48 percent above average (9.43 inches).

As of early April, Breck is on track to record its ninth-snowiest winter. As recently as 2005-2006, 196.3 inches had piled up by this time of year. Other winters with more snow include:

1995-1996: 204.4 inches
1996-1997: 171.1 inches
2005-2006: 196.3 inches
2007-2008: 177.3 inches
1982-1983: 168.9 inches

The all-time record for Breckenridge dates way back to 1898-1899, with 377.7 inches of snow.

summitcountyvoice.com/2011/04/04/summit-...w-5-months-straight/

This year we had less than normal and higher temperatures. That's the thing about weather Raees - it varies year to year. A colder wetter year is no more indicative of global cooling than a warmer drier year is indicative of global warming. We've had above average snowfall for 5 of the last 17 years. We've probably had a similar number of years with below average snowfall and about the same number of years with around average snowfall. That's what averages are after all, right? Sometimes droughts last multiple years, sometimes they last a single year, sometimes we go years without experiencing a drought. It's just the way things are Raees - as much as we might wish otherwise, nature isn't a constant.