31 January-4 February 2011

ITEMS OF INTEREST

• Super Bowl "climatology" -- Next Sunday (4 February 2011) is "Super Sunday" when the Green Bay Packers play the Pittsburgh Steelers in the National Football League's Super Bowl XLV at the new Cowboys Stadium in Arlington, TX. The service climatologist for the Southeast Regional Climate Center has assembled an annotated pdf file listing the weather conditions at kickoff time for each of the previous 44 Super Bowl games (1967-2010); during that span, the games have been played in 12 different metropolitan areas. The climatology for the Dallas-Ft. Worth metropolitan area, the site of the 2011 Super Bowl is also available as a pdf file.
• Groundhog Day and the coming of spring --
This coming Wednesday (2 February 2011) is Groundhog Day, a day coinciding with an ancient late winter festival marking the half-way point between the Northern Hemisphere winter solstice (21 December 2010) and the spring equinox (20 March 2011). According to legend that developed in northern Europe, early farmers would celebrate Groundhog Day by watching for a badger to emerge from hibernation at sunrise. The legend that evolved was that if the animal emerged from its burrow after hibernation on this day and saw its shadow, it would return to hibernation, thereby indicating six more weeks of wintry weather. Most people assume that a converse holds true - if no shadow were seen, an early spring should be expected. The National Climatic Data Center has prepared a Groundhog Day report. No convincing statistical evidence appears to support this belief of the prognostic capabilities of the groundhog. The only point that can be considered to have any meteorological significance is that cloud free weather conditions would be responsible for allowing a woodchuck or human to cast a shadow. Such cloud-free weather conditions in early February typically are associated with a cold mass of air that would usually send all but the hardiest resident back into a nice warm shelter. Regardless of what the local groundhog "predicts" the beginning of astronomical spring is still six weeks away.
• Earth scientists in the news --
During the last week, several scientists who specialize in meteorology and oceanography have been noted for their accomplishments:
• The Director of NOAA's National Centers for Environmental Prediction, Dr. Louis W. Uccellini, has been named President-Elect of the American Meteorological Society, for a presidential term that begins in 2012. [NOAA News] (Editor's Note: Dr. Uccellini has long been a friend and champion of the American Meteorological Society's Educational Initiative. Congratulations to a fellow Wisconsin Badger! EJH)
• The NOAA Administrator recently named David Kennedy to be the new NOAA assistant administrator for the National Ocean Service, effective immediately. [NOAA News]
• Several scientists at the National Center for Atmospheric Research (NCAR) received awards at the recent annual meeting of the American Meteorological Society (AMS). These scientists include
  Joseph Klemp who received the 2011 Carl-Gustaf Rossby Research Medal for outstanding contributions to the understanding of the structure or behavior of the atmosphere and the 2011 Charles Franklin Brooks Award for outstanding services to the AMS.
  Brant Foote, director of NCAR’s Research Applications Laboratory, received the 2011 Cleveland Abbe Award for leadership of a major laboratory that has successfully implemented state-of-the-science methods for addressing problems that affect people’s lives.
  NCAR scientist George Bryan received the 2011 Clarence Leroy Meisinger Award, which is given to promising early-career scientists for outstanding ability. [UCAR]

CURRENT CLIMATE STATUS

• State and city weather extremes for November 2010 -- The National Climatic Data Center (NCDC) has posted a listing of some of the notable extremes in temperature, precipitation and other weather elements across the nation for the month of November 2010 "Selected U.S. City and State Extremes for November 2010." Note that this site may be updated during the following several weeks as more data are received and analyzed.

CURRENT CLIMATE MONITORING

• Satellite image shows how Arctic Oscillation is affecting North America -- A map of the North American continent, Greenland and adjoining sections of eastern Siberia shows the distribution of temperature anomalies (arithmetic differences between observed and long-term averages) during an eight-day span in mid January across the region's land areas as obtained from the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument on NASA's Aqua satellite. The temperature distribution indicates above average temperatures (red areas) across the Arctic Basin, extending from Siberia across Alaska and northern Canada to western Greenland, while below average temperatures (blue areas) prevailed across western Canada and most of the coterminous United States. This pattern reflects a climate pattern known as the "negative phase" of Arctic Oscillation (AO), where the air pressure patterns permit arctic air to push southward across sections of the North American continent, while mild air invades sections of the Arctic. [NASA Earth Observatory]
• Polar mesospheric clouds becoming more numerous and brighter --
An atmospheric scientist at NASA's Goddard Space Flight Center reports that his analysis of data collected by Solar Backscatter Ultraviolet instruments onboard NASA satellites indicates an increase in the number and the brightness of polar mesospheric or noctilucent clouds over the last 31 years. During recent decades, these clouds, which are found in the polar mesosphere (altitudes of approximately 50 miles), have become more easily visible, possibly because of increased amounts of mesospheric water vapor and lower temperatures at that altitude. [NASA Earth Observatory]
This scientist has also provided a display of the noctilucent clouds over the Northern Hemisphere's polar cap obtained from the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite taken over slightly more than an eight hour time span. [NASA Earth Observatory]
• Field testing a remote-sensing instrument reaches a milestone --
NASA scientists have noted that an instrument called the High Spectral Resolution Lidar (HSRL) has been flown on a research aircraft for more than 1000 hours as part of field testing, which began in late December 2005. This remote-sensing instrument has collected atmospheric aerosol data from across North America and the Caribbean for intercomparisons with a similar instrument onboard NASA's Earth-orbiting Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite. The data collected are important for monitoring changes in the planet's weather and climate. [NASA Langley Research Center]
• Performance tests continue on salinity-measuring satellite --
Engineers from NASA's Jet Propulsion Laboratory have been conducting performance tests on the instrument package that is a part of the Aquarius/Satelite de Aplicaciones Cientificas (SAC-D) spacecraft that will be launched in early June. Aquarius/SAC-D, an international mission involving NASA and Argentina's space agency (Comisión Nacional de Actividades Espaciales), is designed to measure global sea surface salinity (dissolved salt concentration) and its variability for climate studies, since salinity is a key tracer for ocean circulation. [NASA JPL]
• An All-Hazards Monitor --
This Web portal provides the user information from NOAA on current environmental events that may pose as hazards such as tropical weather, fire weather, marine weather, severe weather, drought and floods. [NOAAWatch]
• Global and US Hazards/Climate Extremes --
A review and analysis of the global impacts of various weather-related events, including drought, floods and storms during the current month. [NCDC]

CLIMATE FORCING

• Debris on Himalayan glaciers may prevent melting -- Using new remote-sensing techniques and satellite images, researchers at the University of California, Santa Barbara claim that rocks, pebbles and other debris strewn on the surface of glaciers in Asia's Himalayan Mountains may prevent the melting of the glaciers. Glacial melt from these mountains affects water supplies for the hundreds of millions of residents of South Asia. [University of California, Santa Barbara]
• Greenland ice flow may be slowed --
Using five years of satellite data to assess the mass budget of six Greenland glaciers, scientists at the United Kingdom's University of Leeds and the University of Sheffield and the University of Utrecht in The Netherlands claim that the ice flow from some Greenland glaciers run slower in warm summers than in cooler summers. These findings could indicate that the ice cap may be more resistant to the effects of global warming than previously assumed. [BBC News]
• Warming North Atlantic water could be linked to Arctic heating --
Scientists from Germany and the University of Colorado, Boulder have report that temperatures of North Atlantic Ocean water flowing north into the Arctic Ocean through the Fram Strait are the highest in over 2000 years and appear related to the amplification of the widespread warming in the Arctic basin. They believe that the rapid Arctic warming and the decrease in the extent of Arctic sea ice are coupled with enhanced heat transfer from the North Atlantic Ocean. [University of Colorado, Boulder]

CLIMATE AND THE BIOSPHERE

• Smaller soybean rows could increase higher yields in colder climes -- A researcher at Cornell University claims that soybeans planted in 7.5-inch rows in the cooler Northeastern United States produced higher yields than those soybeans planted in the more traditional 30-inch rows. [American Society of Agronomy]

CLIMATE FORECASTS

• Drought could become more frequent in eastern Africa -- Scientists from the US Geological Survey and the University of California, Santa Barbara warn that the increased frequency of drought observed across eastern Africa over the last two decades could continue as both the global and Indian Ocean temperatures continue to rise, while regional precipitation diminishes. Increased drought frequency poses a risk of food shortages for more than 17 million people in the Horn of Africa. [USGS Newsroom]

PALEOCLIMATE RECONSTRUCTION

• Links seen between ancient climate change and mass extinction events -- Researchers at the California Institute of Technology have discovered that the Late Ordovician mass extinction (at approximately 450 million years ago) appears to have coincided with a glacial period in Earth history when global temperatures dropped, leading to a possible link between the two events. The researchers used a new isotopic method for measuring ancient ocean temperatures to determine the timing of the glaciation. [Cal Tech]

CLIMATE AND SOCIETY

• Interagency partnership formed for renewable energy modeling and forecasting -- Last week, senior officials with the US Departments of Energy and Commerce signed a new agreement had been made between the two departments to foster collaboration on renewable energy modeling and weather forecasting in an effort to help enable the nation’s renewable energy resources to be used more effectively by business and entrepreneurs. The two agencies will be encouraged to cooperate in the development and dissemination of weather and climate information needed for renewable energy technologies that are dependent on short-term weather and longer-term climate trends. [NOAA News]
• Website for human dimensions of climate change --
An interagency effort within the US federal government that included NOAA, the Bureau of Land Management and the US Forest Service, has resulted in a website called HD.gov (for HumanDimensions.gov) that provides users, such as natural resource managers, with information on the human dimensions on a variety of topics of interest such as climate change. [HD.gov]
• Earthweek --
Diary of the Planet [earthweek.com] Requires Adobe Acrobat Reader.

Concept of the Week: Feedback in Earth’s Climate System

In Earth’s climate system, feedback consists of a process where a change in one variable interacts with other variables of the system to alter that original variable. If the change reinforces the original quantity, it is known as a positive feedback. If the change suppresses the original quantity, it is a negative feedback. Feedbacks in Earth’s climate system are significant—thought to be responsible for more than half the global warming expected from human activities.

Consider examples of positive and negative feedback. A warming trend in climate is likely to accelerate the rate of melting of snow and ice, producing more bare ground that absorbs more solar radiation, further raising the air temperature. A cooling trend prolongs snow and ice cover in spring and summer so that less solar radiation is absorbed, more reflected to space, bringing about additional cooling. In both cases, feedback is positive because the initial change in temperature is amplified.

Consider an example of negative feedback. While feedbacks among temperature, cloud cover, and radiation are not well understood and depend upon circumstances (e.g., type and height of clouds), they could be either positive or negative. It is thought that a warming trend in climate should increase the rate of evaporation of water from Earth’s surface and thereby increase low cloud cover. A thicker and more extensive low-cloud cover reflects more solar radiation to space thereby inhibiting a further rise in surface temperature. Hence, this negative feedback would dampen the initial temperature change.

Understanding feedback in the climate system is essential for modeling and predicting climate change. If some agent or mechanism alters the climate, then feedback may either amplify (positive feedback) or dampen (negative feedback) the change in climate. As demonstrated later in this course, many agents and mechanisms can bring about climate change (e.g., variations in solar energy output, regular fluctuations in Earth-Sun geometry). While these climate forcing agents and mechanisms drive climatic change, processes within the planetary climate system involving feedbacks significantly impact the magnitude of climate change.

Overall, which type of feedback prevails in Earth’s climate system, positive or negative? A system in which positive feedback prevails is unstable. For Earth, this would move the climate regime toward an extreme characterized by excessive cold that would encase the planet in snow and ice ("snowball" or "ice ball" Earth) or toward the other extreme resulting in much higher temperatures—the product of a runaway greenhouse effect. Although Earth’s climate has varied considerably over the billions of years that constitute geologic time, it appears likely that Earth’s climate system has been nearly stable with negative feedbacks generally compensating for positive feedbacks.

Concept of the Week: Questions

Place your responses on the Chapter Progress Response Form provided in the Study Guide.

1. The magnitude of a climate change [(largely depends upon)(is independent of)] positive and negative feedback phenomena operating in Earth’s climate system.
2. Through much of Earth history, it appears that [(positive feedbacks)(negative feedbacks)(a general balance between positive and negative feedbacks)] have (has) prevailed.

Historical Events:

• 31 January 1911...Tamarack, CA was without snow the first eight days of the month, but by the end of January had been buried under 390 inches of snow, a record monthly snowfall total for the U.S. (The Weather Channel)
• 31 January 1920...The highest barometric pressure observed in the contiguous forty-eight states was recorded at Northfield, VT with a reading of 31.14 inches of mercury (1054.5 millibars). (The Weather Doctor)
• 31 January 1963...The Mt. Rose Highway Station near Reno, NV reported 7.13 inches of precipitation, which set a 24-hour maximum precipitation record for Nevada. (NCDC)
• 31 January 1989...The barometer rose to 31.85 inches of mercury (1079.7 millibars) at Northway, AK, establishing the all time highest reading for the North American continent. (The Weather Doctor)
• 31 January 1994...Caribou, ME recorded its coldest month ever. The average temperature for the month was a frigid 0.7 degrees below zero. The old record was 1.3 degrees set in January 1957. (Intellicast)
• 1 February 1985...The temperature at Gavial, NM dropped to a state record low of 50 degrees below zero. The state record low temperature in Colorado of 60 degrees below zero was tied at Maybell. A station at Peter's Sink, UT reported a temperature of 69 degrees below zero, which set the all-time state record. (NCDC)
• 2 February 1951...The record low temperature for the state of Indiana was set at Greensburg when the mercury fell to 35 degrees below zero; this record was broken in January, 1994. (Intellicast)
• 2 February 1952...The only tropical storm of record to hit the U.S. in February moved out of the Gulf of Mexico and a cross southern Florida. It produced 60-mph winds, and two to four inches of rain. (2nd-3rd) (The Weather Channel)
• 2 February 1996...Extremely cold air covered the north-central U.S. Tower, MN dropped to 60 degrees below zero to set a new state low temperature record. International Falls, MN and Glasgow, MT both set records for the month of February with 45 and 38 below zero, respectively. Rochester, MN dipped to 34 below zero for its lowest temperature in 45 years. Green Bay, WI only reached 16 degrees below zero for the high temperature for the day, which is its lowest high temperature on record in February. Meanwhile, farther to the east, heavy snow fell across the mid-Atlantic region. Eighteen inches of snow was recorded at Rehoboth Beach, DE and 17 inches fell at Solomons, MD. Charleston, WV recorded 6.8 inches of snow for the day to bring its seasonal snowfall to 80.7 inches, the city's snowiest winter ever -- and still two months of winter to go! (Intellicast)
• 3 February 1917...Downtown Miami, FL reported an all-time record low of 27 degrees. Miami weather records date to 1911. (David Ludlum)
• 3 February 1947...The temperature at Tanacross, AK plunged to a record 75 degrees below zero. (David Ludlum) At Snag, Yukon Territory, the temperature fell to 81 degrees below zero, North America's lowest recorded official temperature (The Weather Doctor)
• 3 February 1996...Extremely cold weather persisted. Des Moines, IA dipped to 26 degrees below zero to tie its February low and broke its record for most consecutive hours below zero, which ended up being 132 hours. Milwaukee, WI also tied its record for lowest February temperature with 26 degrees below zero. The temperature at Tower, MN fell to 60 degrees below zero to set a new all-time state minimum temperature record for the Gopher State. The state record low was also tied in Iowa with Elkader reporting a frigid 47 below zero. Elizabeth, IL recorded 35 degrees below to tie the state lowest temperature record; this record has since been broken in January 1999. (Intellicast) (NCDC)
• 3 February 1997...Centralia, WA set the state record for consecutive days of measurable precipitation at 55 between 10 November 1996 and 3 February 1997. (The Weather Doctor)
• 4 February 1996...Frigid temperatures continued over the northern US and spread southward to the Gulf Coast. A cooperative observer near Couderay, WI reported a temperature of 55 degrees below zero, which set a new record low for the Badger State. This reading is also the lowest temperature ever recorded east of the Mississippi River. Amasa, MI checked in with 51 degrees below zero, which tied the record low for Michigan. Tulsa, OK had a morning low of 11 degrees below zero for its lowest temperature in 66 years. Muskegon, MI recorded an all-time low of 19 degrees below zero. La Crosse, WI completed it longest stretch of subzero temperatures ever (144 hours). The center of the frigid arctic high-pressure system moved over Louisiana, setting an all-time record high barometric pressure of 30.82 inches (1043.6 millibars) at Baton Rouge. (Intellicast)
• 5 February 1887...San Francisco, CA experienced its greatest snowstorm of record. Nearly four (3.7) inches were reported in downtown San Francisco, and the western hills of the city received seven inches. Excited crowds went on a snowball-throwing rampage. (David Ludlum)
• 5 February 1996...The "great arctic outbreak of '96" began to wind down, but not before one more frigid morning. Greene, RI reported a state record low temperature of 25 degrees below zero. (Intellicast)
• 6 February 1933...The temperature at Oimekon, Russia fell to 90 degrees (Fahrenheit), tying the previous lowest recorded temperature in Asia set in 1892. (The Weather Doctor)
• 6 February 1933...The highest reliably observed ocean wave was seen by crew of the US Navy oiler, USS Ramapo, in the North Pacific during the night on its way from Manila to San Diego. The wave was estimated (by triangulation) to have a height of 112 feet. Average winds at the time were 78 mph. (Accord's Weather Guide Calendar)
• 6 February 1978...A massive nor'easter buried the cities of the northeastern U.S. The Boston, MA area received 25 to 30 inches in "The Great New England Blizzard of '78" By the time the storm ended late on the 7th, Boston had 27.1 inches of new snow to set an all-time single storm snowfall record. (David Ludlum) (Intellicast)

Return to DataStreme ECS website

Prepared by Edward J. Hopkins, Ph.D., email hopkins@meteor.wisc.edu
© Copyright, 2011, The American Meteorological Society.