ScienceMag: Medieval Warm Period global, 0.65 °C warmer than present: ‘The largest ocean was 2 °C warmer than today when ancient civilizations exploded’

The authors argue that the Pacific temperatures used to be much warmer sometime during the Holocene (last 11,700 years). For example, some 6,000 years ago, we had the middle Holocene Thermal Maximum. That’s when the great civilizations were born and the Pacific waters near Antarctica and North Pacific were 2.1 °C and 1.5 °C warmer than in the 20th century, respectively! (The error margin is said to be 0.4 °C in both cases.)…

New paper debunks claims that fossil fuel use could cause a mass extinction: Published in Palaeogeography, Palaeoclimatology, Palaeoecology finds that ‘The total amount of carbon needed [to cause a mass extinction] exceeds the modern fossil fuel reservoir’

New paper debunks claims that fossil fuel use could cause a mass extinction

http://hockeyschtick.blogspot.com/2013/10/new-paper-debunks-claims-that-fossil.html

Climate alarmists have claimed that Earth is on its way to the 6th mass extinction as a result of use of fossil fuels. However, a paper published today in Palaeogeography, Palaeoclimatology, Palaeoecology finds that “The total amount of carbon needed [to cause a mass extinction] exceeds the modern fossil fuel reservoir.” In other words, even if the highly-exaggerated effects of CO2 on climate were correct, and even if the entire reserve of fossil fuels was burned, a mass extinction from climate change still would not occur.

Initial assessment of the carbon emission rate and climatic consequences during the end-Permian mass extinction

Ying Cuia, , , , 
Lee R. Kumpa, 
Andy Ridgwellb

a Department of Geosciences and Earth System Science Center, Pennsylvania State University, University Park, PA 16802, United States
b School of Geographical Sciences, University of Bristol, University Road, Bristol BS8 1SS, UK

Highlights

We model the carbon isotope record of the Permian-Triassic event in a novel way.

The result is a continuous record of carbon addition and extraction.

The peak rate of carbon addition is smaller than the present fossil fuel burning rate.

The total amount of carbon needed exceeds the modern fossil fuel reservoir.

Determining the source of carbon needs better constraints on the ocean temperature.

Abstract

Numerous lines of geochemical and stable isotopic evidence indicate that the end-Permian mass extinction was accompanied by abrupt climate change induced by CO2 addition. Catastrophic end-Permian Siberian volcanism may have released a large amount of CO2 into the atmosphere and pushed the Earth’s system beyond a critical threshold, causing the mass extinction. However, the injection rate, total amount and source of CO2 are largely unknown. We conducted a suite of simulations using the recently published carbon isotope records and U–Pb ages from Meishan section in Zhejiang province, China. An Earth System Model of Intermediate Complexity (cGENIE; http://www.genie.ac.uk) was used to extract the pattern of CO2 release needed to replicate the observed carbon isotope excursion across the Permian-Triassic boundary. This analysis leads us to suggest that the source of CO2 must have been significantly heavier than typical biogenic or thermogenic methane to explain the significant warming that occurred during and after the extinction event. Nevertheless, as with the Paleocene-Eocene Thermal Maximum, end-Permian rates of CO2 addition were likely small compared with modern fossil-fuel …

New study finds the natural Pacific Decadal Oscillation controls tornado activity, not CO2 – ‘Higher CO2 is correlated with fewer severe tornadoes’

New study finds the natural Pacific Decadal Oscillation controls tornado activity, not CO2

http://hockeyschtick.blogspot.com/2013/10/new-study-finds-natural-pacific-decadal.html

A new study finds that the severity and locations of tornadoes is strongly influenced by the natural Pacific Decadal Oscillation, with more severe tornadoes occurring during the warm phase and fewer during the cold phase. The cold phase of the 60-year Pacific Decadal Oscillation [PDO] started in the year 2000, and would explain why the US is currently experiencing the fewest tornadoes on record, and why higher CO2 is correlated with fewer severe tornadoes. 

CO2 has nothing to do with tornadoes

Pacific Ocean Temperature Influences Tornado Activity in US

Oct. 17, 2013 — Meteorologists often use information about warm and cold fronts to determine whether a tornado will occur in a particular area. Now, a University of Missouri researcher has found that the temperature of the Pacific Ocean could help scientists predict the type and location of tornado activity in the U.S.

Laurel McCoy, an atmospheric science graduate student at the MU School of Natural Resources, and Tony Lupo, professor and chair of atmospheric science in the College of Agriculture, Food and Natural Resources, surveyed 56,457 tornado-like events from 1950 to 2011. They found that when surface sea temperatures were warmer than average, the U.S. experienced 20.3 percent more tornadoes that were rated EF-2 to EF-5 on the Enhanced Fuijta (EF) scale. (The EF scale rates the strength of tornadoes based on the damage they cause. The scale has six category rankings from zero to five.)

McCoy and Lupo found that the tornadoes that occurred when surface sea temperatures were above average were usually located to the west and north of tornado alley, an area in the Midwestern part of the U.S. that experiences more tornadoes than any other area. McCoy also found that when sea surface temperatures were cooler, more tornadoes tracked from southern states, like Alabama, into Tennessee, Illinois and Indiana.

“Differences in sea temperatures influence the route of the jet stream as it passes over the Pacific and, eventually, to the United States,” McCoy said. “Tornado-producing storms usually are triggered by, and will follow, the jet stream. This helps explain why we found a rise in the number of tornadoes and a change in their location when sea temperatures fluctuated.”

In the study, McCoy and Lupo examined the relationship between tornadoes and a climate phenomenon called the Pacific Decadal Oscillation (PDO). PDO phases, …

Polar Bear expert: September sea ice ballyhoo and why it doesn’t matter to polar bears – ‘It is the extent in June that is important to polar bear survival. June is the end of the critical spring feeding period for polar bears – healthy bears eat more seals over a shorter period of time from March to June than any other time of year’

September sea ice ballyhoo and why it doesn’t matter to polar bears

http://polarbearscience.com/2013/10/20/september-sea-ice-ballyhoo-and-why-it-doesnt-matter-to-polar-bears/

The end of September sea ice summary from the US National Snow and Ice Data Center (NSIDC) finally became available late last week (October 3, “A better year for the cryosphere”).
The summary figure NSIDC provides are the average ice extent for the month (not the maximum achieved at the end of the month), which are compared to previous years.
[There has been considerable ice growth since the end of September (updated daily here].
Here is why the September extent doesn’t matter to polar bears: it is the extent in June that is important to polar bear survival. June is the end of the critical spring feeding period for polar bears (see previous post here) – healthy bears eat more seals over a shorter period of time from March to June than any other time of year. After the end of June, most bears have enough fat to survive a fast of 4 months or more.
In contrast to September – when many bears are taking a time-out on shore – ice extent for June over the last 30 years or so provided an extensive hunting platform for polar bears throughout the Arctic. To show you how extensive, I’ve constructed a composite of ice maps from selected years (Fig.1, below).

Figure 1. Sea ice extent averages for June: 1979 (top left), 1996 (bottom left), 2010 (top right) and 2013 (bottom right). Note that even during the lowest extent on record for June (2010, 10.8 m km2), there was still a considerable amount of ice remaining in all regions where polar bears reside, including Hudson Bay (HB), Davis Strait (DS), East Greenland (EG), Baffin Bay (BB), Barents Sea (BS), Chukchi Sea (CS) and Southern Beaufort Sea (SB), noted on the 1979 map (top left). Maps from NSIDC archive. Click to enlarge.
A bit of variation over time occurred in June but not much: down from 12.6 million kilometers squared in 1979 to 10.8 in 2010, and back up to 11.6 in 2013.
Most importantly, even at the lowest point (2010, 10.8 m km2), there was still considerable amounts of ice remaining in all regions where polar bears reside, including Hudson Bay, Davis Strait, East Greenland, Baffin Bay, Barents Sea, Chukchi Sea and Southern Beaufort Sea.

Here are the numbers (in millions of square kilometers):
June (range 10.8-12.7, a …

New Study: ‘2013 ranks as one of the least extreme U.S. weather years ever’– Many bad weather events at ‘historically low levels’

[Also see: Gore still warning of ‘extreme’ weather, ‘increasing storms’ and ‘other extreme events]

#

Prof. Roger Pielke Jr.: ‘Interesting from @TheSIWeather 2013 ranks as one of the least extreme US weather years ever’

According to the latest analysis of data by the The SI Organization, Inc.

18 OCT/13 FRI

11:50 AM | 2013 – a year with minimal extreme weather events in the US

There have been many forecasts in the news in recent years predicting more and more extreme weather-related events in the US, but for 2013 that prediction has been way off the mark. Whether you’re talking about tornadoes, wildfires, extreme heat or hurricanes, the good news is that weather-related disasters in the US are all way down this year compared to recent years and, in some cases, down to historically low levels.

To begin with, the number of tornadoes in the US this year is on pace to be the lowest total since 2000 and it may turn out to be the lowest total in several decades. The table below lists the number of tornadoes in the US for this year (through 10/17) and also for each year going back to 2000.
(Source: NOAA, http://www.spc.noaa.gov/climo/online/monthly/newm.html)

Year         # of Tornadoes
2013                    771
2012                   1119
2011                   1894
2010                   1543
2009                   1305
2008                   1685
2007                   1102
2006                   1117
2005                   1262
2004                   1820
2003                   1374
2002                    938
2001                   1219
2000                   1072

Second, the number of wildfires across the US so far this year is on pace to be the lowest it has been in the past ten years and the acreage involved is at the second lowest level in that same time period (table below).
(Source: National Interagency Fire Center; http://www.nifc.gov/)

2013            Fires: 40,306           Acres: 4,152,390
2012            Fires: 67,774           Acres: 9,326,238
2011            Fires: 74,126           Acres: 8,711,367
2010            Fires: 62,471           Acres: 3,233,461
2009            Fires: 78,792           Acres: 5,921,786
2008            Fires: 80,094           Acres: 5,254,109
2007            Fires: 85,822           Acres: 9,321,326
2006            Fires: 96,358           Acres: 9,871,939
2005            Fires: 66,552           Acres: 8,686,753
2004            Fires: 63,608           Acres: 8,097,880
*2013 data through 10/16

In addition to wildfires, extreme heat is also way down across the US this year. In fact, the number of 100 degree days across the country during 2013 is not only down for this year, but it is perhaps going to turn out to be the lowest in about 100 years of records.

100_deg_days
(Source: NOAA, USHCN reporting stations; through August)

The …