WEEKLY CLIMATE NEWS

DataStreme ECS WEEK THREE: 21-25 September 2009

ITEMS OF INTEREST --

The Autumnal Equinox -- The Autumnal Equinox will occur this Tuesday afternoon (officially at 2118Z, 22 September 2009 or 5:18 PM EDT or 4:18 PM CDT, etc.). At that time the noontime sun will appear directly above the equator, representing one of the two times during the year for such an occurrence, with the other being at the vernal equinox in March. The term "equinox" arises from the fact that this time of year represents "equal night" and equal day essentially everywhere. Within the subsequent several days, the length of daylight will become noticeably shorter. This decrease in daylight will continue for another three months to the winter solstice during the midday of Monday, 21 December 2009.
Editor's note: John White, a meteorologist from North Carolina involved with the AMS Education program, reported that the geosynchronous (or geostationary) satellites make an "satellite eclipse" of the sun near the spring and autumnal equinoxes because of their equatorial orbit, such that these satellites pass through the earth's shadow and the satellite is powered down when the solar array does not receive sufficient sunlight. [For more information, consult NWS Southern Region GOES Satellite FAQ] EJH.
Lunar orbiter finds extremely low temperatures -- In making a detailed map of the temperatures of the Moon's surface from data collected by the Diviner Lunar Radiometer Experiment instrument onboard NASA's Lunar Reconnaissance Orbiter, scientists have found that the brightness temperature within a crater near the lunar South Pole was -238 degrees Celsius (-397 degrees Fahrenheit), one of the lowest temperatures ever observed on any planet or satellite in our solar system. [NASA JPL News]
Space age fire watch -- A recent image obtained by the MODIS image on NASA's Aqua satellite shows the extent of the area near Los Angeles, CA that was burnt by the Station Fire, which still burns across the region. [NASA Earth Observatory]
The same sensor also captured the smoke from wildfires across Africa's Mozambique last week. [NASA Earth Observatory] A MODIS sensor on NASA's Terra satellite shows the smoke from wildfires in Indonesia's Borneo. [NASA Earth Observatory]

CURRENT CLIMATE MONITORING

Global review of August and boreal summer season -- Basing their analysis on preliminary data, scientists at NOAA's National Climatic Data Center recently reported that the sea surface temperature of the world's oceans were the highest for any August, as well as for any boreal summer/austral winter (the three months of June, July and August) since widespread reliable climate data became available in 1880. The combined global land and ocean average temperature for June through August was the third highest on record, while that for August was the second highest.. [NOAA News]
Monitoring this summer's Arctic sea ice extent -- An image obtained nearly ten days ago from the Advanced Microwave Scanning Radiometer for EOS sensor on NASA’s Aqua satellite shows the extent of the Arctic sea ice at that time. [NASA Earth Observatory] Researchers at the University of Colorado at Boulder's National Snow and Ice Data Center report that as of mid September, the extent of Arctic sea ice appears to have reached a minimum for the 2009 summer season, with an areal extent that was the third smallest since routine satellite surveillance commenced in 1979. [University of Colorado] [National Snow and Ice Data Center]
Keeping track of this year's Antarctic "Ozone Hole" -- As spring begins across the Southern Hemisphere, attention is focused on the size of the annual Antarctic "Ozone Hole," an area of depleted ozone concentrations in the stratosphere that typically expands over Antarctica in austral spring. Scientists at NASA's Goddard Space Flight Center report that data collected from the Ozone Monitoring Instrument on NASA's Aura spacecraft, the Global Ozone Monitoring Experiment on the European Space Agency's ERS-2 spacecraft and the Solar Backscatter Ultraviolet instrument on the NOAA-16 satellite indicates the size of this year's annual hole appears to be comparable with previous seasons in the last decade. [NASA]
A top-down view of glacial flow in Greenland -- An image obtained from the Advanced Land Imager on NASA’s Earth Observing-1 (EO-1) satellite at the end of August shows the detailed flow pattern of glaciers in a valley of western Greenland. [NASA Earth Observatory]
First anniversary of "smog blog" noted -- Early last week, officials from NASA, the U.S. Agency for International Development (USAID), the U.S. Environmental Protection Agency and their partners celebrate the first anniversary of the Mesoamerica and Caribbean "Smog Blog", an air quality initiative within SERVIR that provides in-situ, satellite-based, and modeled air quality data to forecasters, researchers, broadcasters, and communities throughout Mesoamerica and the Caribbean. [NASA Earth Observatory]
Satellites could be used to help feed world's population -- A review article highlights the work done by scientists at NASA's Goddard Space Flight Center to monitor the health of the world's vegetation from NASA satellites, which resulted in the developed the Normalized Difference Vegetation Index (NDVI), a numeric indicator of the changes in the "greenness" of Earth as viewed from space. Scientists and government planners can then use these NDVI images, which are routinely updated, to track droughts, crop infestations, and crop failures in an attempt to avert widespread famine. [NASA GSFC]

CLIMATE FORCING

What's blowing in the solar wind -- Solar scientists at the High Altitude Observatory of the National Center for Atmospheric Research (NCAR) and the University of Michigan have found that high levels of solar energy as part of the solar wind have bombarded the Earth's atmosphere during the last year, a time when the Sun was in an unusually quiet phase with essentially no sunspots. [UCAR/NCAR]

CLIMATE AND THE BIOSPHERE

Warmer climate found to affect spring flowers -- In research conducted at Australia's Monash University and Scotland's University of Edinburgh, the flowering times of spring plants could be impacted by the effects of higher global temperatures, resulting in projected dates of blooming earlier by as much as 50 days in the year 2080. [EurekAlert!]
Changes in climate cause birds in the Sierra to move -- Biologists at the University of California, Berkeley in collaboration with Audubon California have found that approximately 90 percent of the native bird species they studied in California's Sierra Nevada Mountains have responded to the changes to a warmer and wetter climate during the last century by moving to sites where temperature and precipitation conditions were more favorable to them. [EurekAlert!]
An uncertain future foreseen for nation's forests -- Researchers at the University of Illinois and colleagues elsewhere warn that the composition of some of the nation's forests could change significantly in the next several centuries because of climate-driven changes in the temperature and the amounts of photosynthetically active radiation during this time span. [EurekAlert!]

CLIMATE FORECASTS

Three-month outlook released -- Last week, forecasters with NOAA's Climate Prediction Center released their three-month temperature and precipitation outlooks for the nation, running from October through December 2009. Their temperature probability outlook indicates that the western half of the coterminous US (including much of Alaska) should expected a better to much better than even chance of above average temperatures. For those in the eastern half of the nation, equal chances of below and above average temperatures for the rest of the year should be anticipated. The precipitation probability outlook suggests that the southern Plains and the Gulf Coast could experience more than even chances of above average rainfall, while the Pacific Northwest should stand a good chance of remaining drier than average. Elsewhere, equal chances of below and above average precipitation are forecast. This outlook is based on what is seen as a strengthening El Niño episode in the equatorial Pacific Ocean. [Climate Prediction Center]
The Climate Prediction Center also released its US Seasonal Drought Outlook that will run for the rest of the 2009 calendar year. This outlook indicates improvement in the drought conditions across the Southeast, Texas and northern Arizona, while some limited improvement could occur across the Upper Midwest, the Southwest, California and Nevada. Drought conditions were anticipated to persist or develop across the Northwest.
Climate change could result in less UV radiation in the Northern Hemisphere's polar latitudes -- Physicists at Canada's University of Toronto have discovered that changes in the stratospheric ozone layer associated with changes in upper atmospheric circulation patterns due to climate change will reduce the intensity of ultraviolet (UV) radiation in those regions surrounding the Arctic basin such as northern Canada, Scandinavia and Siberia, even though the tropics and Antarctica should expect increasing levels of UV radiation. [University of Toronto]

PALEOCLIMATE RECONSTRUCTION

Mapping of Greenland ice sheet melt conducted -- Researchers from Denmark, Canada, France and Russia who have been studying ice cores obtained from the several different locations on the Greenland ice sheet and adjacent smaller ice caps have found that each core reveals different climate histories over the last 11,700 years. They note that the small ice caps are stable with little change in elevation, whereas the elevation of the main Greenland ice sheet appears sensitive to temperature. [EurekAlert!]

CLIMATE AND SOCIETY

World War I era flu pandemic and El Niño event linked -- Researchers at Texas A&M University believe that their research indicates that a relationship exists between an unusually strong El Niño event in 1918 and a severe flu pandemic, sometimes called the "Spanish Flu" that took millions of lives around the world during the final months of World War I. They feel that the El Niño event, an event with anomalous atmospheric and oceanic circulation patterns favoring warmer than normal temperatures of the surface waters across the eastern equatorial Pacific Ocean, created a severe drought across India, which could have resulted in famine and the rapid spread of influenza across south Asia. [EurekAlert!]
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]
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]
Earthweek -- Diary of the Planet [earthweek.com] Requires Adobe Acrobat Reader.

Concept of the Week: Calendars and Seasons

Humans have used the idea of time to mark past experiences and anticipate future happenings. To quantify time, we have traditionally used observable periodic natural phenomena, such as the daily and yearly paths of the apparent sun through the sky and the monthly phases of the moon. As we saw in the Case-In-Point for Chapter 3, ancients in northern Europe, North America and elsewhere had developed astronomical calculators that located the sun's path at certain key dates during the year.

The sun is especially important as its uneven heating distribution drives Earth's climate system. The orbital points of the solstices and equinoxes define portions of the year in terms of the solar input into the Earth's energy balance, yielding the so-called astronomical seasons. From the viewpoint of the astronomical seasons, we are at the start of fall, since astronomical autumn starts on Tuesday of this week with the passage of the Autumnal Equinox (22 September 2009) and will continue to the Winter Solstice during the third week of December.

Similar to the astronomical seasons, we can define meteorological/climatological seasons that are meant to fit our calendar as well as the temperature cycle. With this designation, we are now in fall. The current transition interval, "autumn", between the year's warmest and coldest portions of the year can be closely linked to the calendar months of September, October and November. Conversely "spring", between the year's coldest and warmest portions is linked to the months March, April and May. Specifically, climate scientists usually compare January and July atmospheric conditions to represent the coldest and warmest months, respectively. We can also have monthly and seasonal averages and records. This information is useful for agriculture, commerce and other purposes.

Concept of the Week: Questions

(Each week you will be asked to respond to two questions relating to that week's Concept of the Week topic. Place your responses on the Chapter Progress Response Form provided in the Study Guide.)

The month was originally based upon cycles of the [(sun)(moon)].
From 5:18 pm EDT on 22 September through 30 November, the Northern Hemisphere will be in its [(astronomical fall)(climatological fall)(both)] season(s).

Historical Events:

22 September 1913...Des Moines, IA experienced their earliest freeze of record. (The Weather Channel)
22 September 1934...Edmonton, Alberta reported its greatest September snowstorm to date with 8.7 inches of snow. (The Weather Doctor).
23 September 1904...The temperature at Charlotteburg, NJ dipped to 23 degrees, the lowest reading of record for so early in the autumn for the state. (The Weather Channel)
24 September 1888...The earliest frost of record hit the southern states covering South Carolina, Georgia and northern Florida (Intellicast)
24 September 1926...The temperature at Riverside Ranger Station in Yellowstone Park dipped to nine degrees below zero, the lowest reading of record in the U.S. during September. (This record was broken by a 15 degree below zero reading at Big Piney, WY in September 1983.) Severe freezes were widespread over the northwestern U.S. causing great crop destruction. In Washington State, Spokane County experienced their earliest snow of record. Harney Branch Experiment Station in Oregon reported a temperature of 2 degrees above zero to establish a state record for the month of September. (David Ludlum) (The Weather Channel)
24-26 September 1950...A smoke pall from western Canada forest fires covered much of the eastern U.S. Daylight was reduced to nighttime darkness in parts of the Northeast. The color of the sun varied from pink to purple, blue, or lavender. Yellow to gray-tan was common. (24^th-30^th) On the 26^th, residents of the northeastern U.S. observed a blue sun and a blue moon from the smoke. (David Ludlum) (The Weather Channel)
25 September 1939...A West Coast hurricane moved onshore south of Los Angeles bringing unprecedented rains along the southern coast of California. Nearly five and a half inches of rain drenched Los Angeles during a 24-hr period. The hurricane caused $2 million in damage, mostly to structures along the coast and to crops, and claimed 45 lives at sea. "El Cordonazo" produced 5.66 in. of rain at Los Angeles and 11.6 in. of rain at Mount Wilson, both records for the month of September. (David Ludlum) (The Weather Channel)
26 September 1963...San Diego, CA reached an all-time record high of 111 degrees. Los Angeles hit 109 degrees. (David Ludlum)
27 September 1816...A black frost over most of New England kills unripened corn in the north resulting in a year of famine. (David Ludlum)

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