Jun

27th 2008

Ice-free North Pole?

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Researchers at the National Snow and Ice Data Center in Boulder, Colorado are predicting that the North Pole may be briefly ice free this summer.  Mark Serreze, a senior research scientist states, “It’s a 50-50 bet that the thin Arctic sea ice, which was frozen last autumn, will completely melt away at the geographic North Pole.“  Serreze blames the condition on global warming noting, “We’ve known for at least 30 years, from our earliest climate models, that it’s the Arctic where we’d see the first signs of global warming.”

Read more: North Pole could be ice-free this summer, scientists say - CNN.com

Mar

26th 2008

Tipping Elements in Climate Warming

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Forbes has an article with a round-up of the earth systems considered by scientists to having tipping points considered a danger to global climate systems.  The tipping points were extracted from an article entitled “Tipping Elements in the Earth’s Climate System,” published in the Proceedings of the National Academy of Sciences. 

Dec

02nd 2007

Bundle up, or not

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Climatologists have a new career path: fashion. In an unlikely teaming, apparel companies are adding climatologists to their design teams to help them plan fashions. The change in weather patterns has thrown the expectation of colder weather in winter out the window. With various regions in the United States registering warmer than usual weather in the traditionally colder months, the art of selling clothes is becoming more of a science. Companies such as Liz Claiborne and Target are hiring meteorologists to help them anticipate weather patterns for upcoming seasons and adjust their fabrics to meet temperature conditions.

Nov

05th 2007

How to read a weather map

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The wiki-based how-to site, wikiHowto has an informative tutorial in deciphering the symbology of a weather map.  The tutorial reviews how to read weather maps in order to interpret pressure systems, fronts and understanding measurements of conditions measure at weather observation stations.

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Oct

16th 2007

How long will the North Pole ice cap last?

Filed Under Climatology, Current Events, Environment | 2 Comments

Pen Hadow of Vanco Artic Survey hopes to answer that question with the most detailed survey ever of the Arctic ice thickness at the North Pole.  Starting next February 2008, a team of scientists and explorers will undertake a 120 -day, 3,200 mile journey to cross the ice cap.  The team will start in Point Barrow, Alaska and reach the polar cap by June, 2008.  Along the way, over 10 million readings will be taken to determine snow and ice thickness.  Currently, estimates on the melting of the ice cap range from 16 to 100 years.  The readings, taken by radar, will help determine a more accurate assessment of the remaining life of the permanent ice cap of the North Pole. 

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Proposed route from Point Barrow to the North Pole

Jun

06th 2007

Paleomap Project

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Created and compiled by Christopher Cortese, from the University of Texas at Arlington, Paleomap Project is a site that uses maps and animation to illustrate earth and climate history.  According to the web site the goal of the web site is to “illustrate the plate tectonic development of the ocean basins and continents, as well as the changing distribution of land and sea during the past 1100 million years.”  3-D animations are also available for viewing as well as teaching materials and ArcView formated software and GIS layers. 

Jan

21st 2007

Impact of relocating weather station in Los Angeles

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A Tale of Two Sites: Impacts of Relocating L.A.’s Weather Station
January 17, 2007 In the classic 1859 novel, “A Tale of Two Cities,” Charles Dickens spins a moral tale of dramatic contrasts between 18th century London and Paris. To modern-day climatologists, though, the story could serve as a metaphor for weather records in Los Angeles since the National Weather Service relocated the city’s official downtown Civic Center weather station to the University of Southern California in July 1999.

A new comparative study of daily temperature and rainfall records in Los Angeles by NASA and university scientists finds the move — to a location nearly 6 kilometers (almost 4 miles) closer to the coast and 27 meters (90 feet) lower in elevation — has produced weather records reflecting conditions that are cooler, drier and less extreme than those at the previous location.

At the annual meeting of the American Meteorological Society in San Antonio, Texas, climatologist Dr. Bill Patzert of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., said the move has created a clear discontinuity in weather records.

“The move from downtown Los Angeles to USC in 1999 has caused a major hiccup in our local climate history,” said Patzert. “Suddenly, Los Angeles became dryer and cooler, and we were denied a record rain year in 2004-2005. The magnitude of change reflected in our study strongly suggests this relocation will bias long-term climatic studies.”

This is hardly the first move of the downtown Los Angeles weather station, but it is by far the largest, and the first to move the station away from the built-up city center. The station was moved from the roof of a two-story parking structure at the Department of Water and Power building near city center at an elevation of almost 90 meters (270 feet), to a park-like environment on the USC campus with tall shade trees and grass at an elevation of almost 60 meters (180 feet).

The National Weather Service moved the station as part of a nationwide effort to locate all official weather stations on ground-level sites in natural settings. The Department of Water and Power site remained operational, however, allowing the direct comparisons used by Patzert and his colleagues.

The study found that between August 1999 and June 2006, maximum temperatures averaged 1 degree Celsius (1.8 degrees Fahrenheit) higher at the Department of Water and Power site, while the average temperatures at the new site were about a half-degree Celsius (0.9 degrees Fahrenheit) warmer. Minimum temperatures were about the same at both sites. The greatest differences in maximum temperatures occurred in late summer and early fall, with the smallest differences seen in late winter and spring. The Department of Water and Power site was cooler than USC in the spring and summer and warmer in the fall and winter. The authors attribute these seasonal differences to two factors: distance from the ocean and land use.

“In southern California, the cool ocean current keeps the coast cooler in summer and milder in winter than inland areas,” said co-author Dr. Steve LaDochy, a climatologist at California State University, Los Angeles. “For example, the Department of Water and Power site averages 1.7 degrees Celsius (three degrees Fahrenheit) warmer than Los Angeles International Airport at the coast, just 20 kilometers (12 miles) away.”

Because of the abundance of trees and grass, the USC station tends to be cooler during the day than the urbanized Department of Water and Power site. At night, the trees can block outgoing radiation, and the moisture in the lawns tends to absorb more heat than the drier, open Department of Water and Power site.

The USC site averaged about 25.4 millimeters (about one inch) less rainfall than the higher and more inland Department of Water and Power location. Again, elevation and distance from the coast are driving factors in the differences. In the Los Angeles basin, rainfall increases with elevation and with distance from the coast. The Department of Water and Power site averages 375 millimeters (14.77 inches) of rain a year, while Los Angeles International Airport averages just 305 millimeters (12.01 inches). Rainfall comes primarily from Pacific winter storms moving inland from a westerly direction. As these storm fronts are lifted by the coastal mountains, rain and snow tend to increase with increasing elevation on the coastal side of the mountains.

The weather station relocation kept Los Angeles from setting a new rainfall record in the 2004-5 water year (from July 1 to June 30). The USC site recorded 946.2 millimeters (37.25 inches), second only to 1883-4, which had 969.8 millimeters (38.18 inches). That same season, the Department of Water and Power site recorded 973.3 millimeters (38.32 inches). Conversely, in 2001-02, the USC station recorded the driest year ever–about 112 millimeters (4.42 inches), a record that would not have occurred without the move.

LaDochy cited the record heat wave of June and July 2006 as an example of how the move has made temperature records less extreme. At the USC station, the all-time record for the highest minimum temperature (overnight low) was set on June 4, with 20 degrees Celsius (68 degrees Fahrenheit). However, that same week, the Department of Water and Power station recorded highest overnight lows three days in a row. Similarly, for the month of July, USC station temperatures broke or tied seven all-time records, while the Department of Water and Power site broke nine.

Since the Department of Water and Power station is still operational, Patzert and his co-authors suggest its records be reinstated as the official Los Angeles downtown station, with the USC station becoming part of the National Weather Service’s Cooperative Observer Program. That program has sites all over the United States, maintained by volunteers or contractors.

Other study authors include JPL’s Dr. Josh Willis and Teni Mardirosian, Glendale Community College, Glendale, Calif.