Senior meteorologist with 20 years of experience at AccuWeather. [ Bio ]
November 2009
| Sun |
Mon |
Tue |
Wed |
Thu |
Fri |
Sat |
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
|
8
|
9
|
10
|
11
|
12
|
13
|
14
|
|
15
|
16
|
17
|
18
|
19
|
20
|
21
|
|
22
|
23
|
24
|
25
|
26
|
27
|
28
|
|
29
|
30
|
|
|
|
|
|
|
New research from NASA suggests that the bulk of nitrogen oxide (NOx) produced during lightning storms ends up significantly higher in the atmosphere, and thus has a stronger impact on ozone and the climate than previously thought.
Photo courtesy of the Accuweather.com photo gallery.
According to the NASA story, there are 1.2 billion lightning flashes in the world per year. Each lightning flash produces a puff of nitrogen oxide gas that reacts with sunlight and other gases in the atmosphere to produce ozone. Near Earth's surface, ozone can harm human and plant health; higher in the atmosphere, it is a potent greenhouse gas.
The image below from NASA shows the annual lightning flash density across the globe. Note the highest concentration is over central Africa. Florida also experiences a great deal of lightning.
It is believed that lightning contributes about 10% of atmospheric nitrogen oxide, which is much smaller compared to fossil fuel emissions, but scientists are still not completely sure if that estimate is correct, and that it may be underdone.
"One of the things we're trying to understand is how much ozone changes caused by lightning affect radiative forcing, and how that might translate into climate impacts," said Kenneth Pickering, an atmospheric scientist who studies lightning at NASA's Goddard Institute for Space Studies.
There's a possibility that lightning could produce a feedback cycle that accelerates global warming. "If a warming globe creates more thunderstorms," Pickering noted, "that could lead to more NOx production, which leads to more ozone, more radiative forcing, and more warming," Pickering emphasizes that this is a theory, and while some global modeling studies suggest this is indeed the case, it has not yet been borne out by field observations.
The growth rate of Arctic sea ice during the first half of October was slowed due to persistent south winds over central Siberia, according to the National Snow and Ice Data Center (NSIDC). The winds prevented sea ice from forming along the Siberian Coast during that time, which allowed the sea ice extent to almost match the record low year of 2007.
Low-level Arctic Temperature anomalies from October
At this time, it does look like the progression of sea ice has resumed a more normal, seasonal increase.
A comparison of Arctic sea ice extent (4 lowest years) from July through early November.
Comparing the October sea ice extents going back to 1979 with trend line.
-----------
All images courtesy of the NSIDC.
Dr. Stephen Schneider, a Stanford University scientist inexplicably withdraws from a new climate change documentary. Why is that? Host Katie Fehlinger of AccuWeather.com's Headline Earth tells the story...............Here is the link to the video.
Climate Depot also has more on this story right here.
----------
My opinion......it has been almost 40 years since his comments about cooling, and opinions change with new data and more computing power. However, it is unfortunate that the University stepped in and prohibited the filmmakers from using the audio and video of Schneider.
No surprise here...........
Research from the Universities of Maryland and Colorado, in addition to Purdue University, has found that a majority of land-use changes in the continental U.S. reduce vegetative cover and raise regional surface temperatures.
Satellite views of different types of agricultural land-use
But, any conversion of land, whether urban or forested, to agricultural use results in cooling, which is most likely due to increased evaporation.
"What we highlight here is that a significant trend, particularly the warming trend in terms of temperatures, can also be partially explained by land use change," said Niyogi, a Purdue earth and atmospheric sciences professor and the Indiana state climatologist, who is the corresponding author of the article, according to the University of Maryland press release.
"I think that greenhouse warming is incredibly important, but land use should not be neglected," said University of Maryland Professor Eugenia Kalnay, one of the study's co-authors. "It clearly contributes to warming, especially in urban and arid areas."
Kalnay also stated that these findings do not negate the effects of greenhouse gases like carbon dioxide.
The University of Maryland was kind enough to break down the specific findings of the research...........
--In general, the more vegetation covering an area of land, the cooler its contribution to surface temperature.
--Local and regional changes in land use more often result in warming than in cooling.
--Urbanization and conversion to bare soils have the largest warming impacts.
--Conversion to agriculture results in cooling, while conversion from agriculture generally results in warming.
--Deforestation generally results in warming, with the exception of a shift from forest to agriculture.
--The temperature effect of planting a new forest is still unclear.
Thanks to the University of Bremen in Germany, we can get a daily update of the sea ice concentration across the Arctic and Antarctic. Here are the latest images from Friday and from exactly one year ago for comparison. The more red and purple, the higher the sea ice concentration.
October 30th, 2009 Arctic
October 30th, 2008 Arctic
It looks like there is less ice north of eastern Europe and northwest of Alaska compared to last year.
October 30th, 2009 Antarctic
October 30th, 2008 Antarctic
From what I can tell, it looks like there is more ice this year compared to last year around the Antarctic Peninsula. But, the concentration of ice between 135 W and 180 degrees is not as high compared to 2008.
---------
The University of Bremen now also charts the sea ice extent of the Arctic and Antarctic and compares the plot of 2009 with each previous year going back to 2003. You can see the annual rise and fall of sea ice extent due to changing seasons.
Arctic
Antarctic
-----------
All maps courtesy of the University of Bremen website.l
Let's check out the latest trend in atmospheric carbon dioxide (C02) courtesy of NOAA. The chart shows the globally averaged atmospheric CO2 concentration averaged over marine surface sites.
The dashed red line with diamond symbols represents the monthly mean values, centered on the middle of each month. The black line with the square symbols represents the same, after correction for the average seasonal cycle.
While you can clearly see that global atmospheric CO2 is still on the rise, it has leveled off a bit in 2009. Perhaps this is due in part to the global recession.
The actual growth rate of atmospheric CO2 is not yet known for 2009, but it was 1.79 ppm/year in 2008, which was down from 2.12 in 2007.
Global concentrations of greenhouse gases
Research posted in the Journal Science and led by Drew Shindell from NASA's Goddard Institute for Space Studies (GISS) claim that too much of the blame in regards to global warming are put on carbon dioxide and not enough on methane.
In the study, Shindell and colleagues added chemical interactions between aerosols and greenhouse gases such as methane and carbon monoxide to a century-long model of climate change. They wanted to see the effects on each gas's "Global Warming Potential," or individual contribution to global warming, according to the USA TODAY article.
Methane played a bigger role than expected, suggesting that climate treaties such as the 1997 Kyoto Protocol need to consider it more carefully, the study says.
"There is no way, other than aggressive geoengineering, to come close to meeting the world leaders goal of overall warming not exceeding (3.6 degrees Fahrenheit) above preindustrial (levels) without focusing on both carbon dioxide and non-carbon dioxide emissions," says Michael MacCracken of the Climate Institute, by email. "This is not an either-or choice, we must do both to have any chance at all."
Now this is an invention that really makes sense..........
A team of recent MIT graduates have developed roof tiles that change color in response to the changing temperature. The tiles will turn white (reflecting the sun's radiation) on a hot day, but turn black (absorbing the sun's radiation) on a cold day.
We have seen in the past a lot of talk about changing our roof color to more white, which would keep our houses cooler in a warming world, but what do you do in the winter when it still gets cold and you still have that white roof? It can end up canceling out the energy savings that you made in the summer.
This invention solves that problem, as the tiles adapt to the changing season. The white tiles keep our houses a little cooler on those hot summer days so that we do not need to use as much AC. According to the LiveScience article that could be as much as a 20% savings in cooling costs. In the winter the black roof allows more of the sun's heat to penetrate into the house, thus allowing us to lower the setting of the thermostat a little bit. The actual amount of savings from a black roof was undetermined at this present time.
This roof tile setup is still not commercial ready, but they are working on it. I would also be curious on the initial cost to install a roof like this.
There have been many recent claims by some scientists and the general public that the Earth is actually cooling. Not so, according to some statisticians.
Global land/sea temperature anomaly trend since 1880. Courtesy NCDC.
30-year satellite measured global temperature anomaly trend. Courtesy of Remote Sensing Systems (RSS).
An analysis of global temperature data by four independent statisticians found no true temperature declines over recent time, according to the Associated Press (AP) story, which provided the data to the statisticians without telling them what the numbers represented.
The AP sent expert statisticians NOAA's year-to-year ground temperature changes over 130 years and the 30 years of satellite-measured temperatures preferred by skeptics and gathered by scientists at the University of Alabama in Huntsville.
The statisticians found a distinct decades-long upward trend in the numbers, but could not find a significant drop in the past 10 years in either data set, according to the AP.
NOAA also re-examined their temperature data and found no cooling trend.
"The last 10 years are the warmest 10-year period of the modern record," said NOAA climate monitoring chief Deke Arndt. "Even if you analyze the trend during that 10 years, the trend is actually positive, which means warming."
John Grego, a statistician from the University of South Carolina produced three charts to show how choosing a starting date can alter perceptions. Using the skeptics' satellite data beginning in 1998, there is a "mild downward trend," he said. But doing that is "deceptive."
The trend disappears if the analysis starts in 1997. And it trends upward if you begin in 1999, he said to the AP.
To find the cooling trend, the 30 years of satellite temperatures must be used. The satellite data tends to be cooler than the ground data. And key is making sure 1998 is part of the trend, said Don Easterbrook, a Western Washington University geology professor and global warming skeptic. According to Easterbrook, it's what happens within the past 10 years or so, not the overall average, that counts.
Saying there's a downward trend since 1998 is not scientifically legitimate, said David Peterson, a retired Duke University statistics professor and one of those analyzing the numbers for the AP.
Sediments from the mid-20th century onward that were retrieved from a remote Arctic lake by geologists from the University of Buffalo are unlike those seen during previous warming episodes going back as far as 200,000 years.
According to the University of Buffalo, the idea that climate change since the mid-20th century might simply be a natural variation like others that have occurred throughout geologic time is dimming.
The research team was able to pinpoint that dramatic changes began occurring in unprecedented ways after the midpoint of the 20th century.
This particular lake was unique, since its sediment cores were not eroded like most lake sediment cores in the Arctic, even though glaciers covered this particular lake in the past.
"The result is that we have a really long sequence or archive of sediment that has survived arctic glaciations, and the data it contains is exceptional," said Jason Briner, a professor of geology at the University of Buffalo.
"The 20th century is the only period during the past 200 millennia in which aquatic indicators reflect increased warming, despite the declining effect of slow changes in the tilt of the Earth's axis which, under natural conditions, would lead to climatic cooling," according to Yarrow Axford, from the University of Colorado and lead author of this paper.
-----------
This study is published in the Proceedings of the National Academy of Sciences.
|
|
