WEEKLY CLIMATE NEWS

DataStreme ECS WEEK FOUR: 22-26 September 2014

ITEMS OF INTEREST

The Autumnal Equinox -- The Autumnal Equinox will occur early this coming Monday evening (officially at 0229Z on 23 September 2014 or 10:29 PM EDT or 9:29 PM CDT, etc. on the 22nd). 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 early evening of Sunday, 21 December 2014.
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.
If you checked the sunrise and sunset times in your local newspaper or from the climate page at your local National Weather Service Office, you would probably find that not until the midpoint of this coming week will the length of time when the Sun is above the local horizon would be precisely 12 hours at most locations. However; the length of night will exceed that of the length of daylight by the end of the week. As discussed in this week's Supplemental Information…In Greater Depth, the effects of atmospheric refraction (bending of light rays by the varying density of the atmosphere) along with a relatively large diameter of the sun contribute to several additional minutes that the sun appears above the horizon at sunrise and sunset.
Monitoring the seasonal motions of the sun -- If you would like more background information concerning how the sun appears to across your local sky, along with the times of local sunrise and local sunset, for your hometown on any day throughout year, please read this week's Supplemental Information…In Greater Depth.

CURRENT CLIMATE STATUS

Review of August 2014 (and seasonal) weather and climate for the globe -- Preliminary data analyzed by scientists at NOAA's National Climatic Data Center (NCDC) indicated:

The global combined land and ocean average surface temperature for August 2014 was 61.45 degrees Fahrenheit, which represents a record high August monthly temperature since a sufficiently dense network of global temperature records began in 1880. The globally averaged August 2014 temperature was 1.35 Fahrenheit degrees above the 20th-century average (1901-2000) for the month. When considered separately, the monthly temperature departure of the ocean surface was 1.17 Fahrenheit degrees above the 20th-century average, which not only would be a record high for August in the last 135 years, but also broke the largest temperature departure for any month of the year, set only two months ago in June 2014. The land surface surface temperature for this recently concluded month was the second highest August temperature on record, with a monthly temperature that was approximately 1.78 Fahrenheit degrees above the 20th-century average. [NOAA/NCDC State of the Climate]
A global map of Selected Significant Climate Anomalies and Events for August 2014 is available from NCDC.
The global land and ocean average temperature for the three-months of June, July and August (meteorological summer in the Northern Hemisphere) 2014 was also the highest for this three-month period since 1880, as it was 1.28 Fahrenheit degrees above the 20th-century average. The June-August 2014 temperature for the ocean was highest while the corresponding land temperature for the three months was the fifth highest for any boreal summer in the last 135 years.
According to data provided by the National Snow and Ice Data Center, the average August Arctic sea ice extent was approximately 13.8 percent below the 1981–2010 average, making it the seventh smallest August Arctic sea ice extent since satellite records began in 1979. Conversely, the August Antarctic sea ice extent was the largest August extent on record.

CURRENT CLIMATE MONITORING

New scatterometer heading to Space Station to monitor ocean winds -- After several delays, the SpaceX commercial resupply services mission's Falcon 9 rocket carrying NASA's International Space Station Rapid Scatterometer (ISS-RapidScat) finally lifted off from Cape Canaveral early Sunday morning. The ISS-RapidScat instrument, which is scheduled to reach the International Space Station on Tuesday, will globally monitor surface winds over the oceans and is intended to track tropical and nontropical cyclones (storms) and help provide a better understanding of climate. [NASA Jet Propulsion Laboratory News]

CLIMATE FORCING

Eyewitness accounts of the "Unknown eruption" uncovered -- A team consisting of a historian and earth scientists at the United Kingdom's University of Bristol recently were able to find eyewitness reports made by early 19th century Latin American scientists in Columbia and Peru of a tropical volcano that erupted in 1808 and was identified as the "Unknown eruption," the second most explosive sulfur dioxide-rich volcanic eruption in the last two centuries. The Unknown eruption, which occurred a few years prior to the famous 1815 Tambora volcanic eruption, helped create a volcanic dust veil that contributed to the cold weather conditions in the second decade of the 19th century. These eruptions helped lead to the "Year without a Summer" in 1816. [University of Bristol News]
Tornadoes appear to occur earlier in "Tornado Alley" -- Scientists at Montana State University have discovered that tornado season in the region of the southern and central Plains known as "Tornado Alley" is starting earlier than 60 years ago. In addition, the peak season for tornado activity in some locations occurs as much as 14 days earlier than in the early 1950s. A warming climate may contribute to the earlier season, along with occurrences of El Niño events during the winter. [Montana State University]

CLIMATE FORECASTS

New Seasonal Climate Outlooks for the remainder of 2014 issued -- Near the end of last week, forecasters at the NOAA Climate Prediction Center (CPC) released their new national Three-Month (Seasonal) Climate Outlooks for October through December 2014, corresponding to the last two months of the meteorological autumn season (in the Northern Hemisphere) and the first month of meteorological winter. Specific details of their outlooks include:
- Temperature and precipitation outlooks -- According to their temperature outlook, most of the contiguous United States should experience a high chance of above average temperatures for these three upcoming months, with the greatest probability of such an occurrence to be found along the West Coast and sections of the Intermountain West. Chances of above average temperatures for the last three months of 2014 also would be better than average along the Atlantic Seaboard and across the Midwest and northern Plains. Conversely, sections of the southern Rockies and adjacent areas of the Southwest and the southern Plains could have a better than even chance of below average temperatures through the end of the year. The outlook indicates that the remainder of the nation extending from the Great Basin to the lower Mississippi Valley would have nearly equal chances of warmer or cooler than normal conditions.
  Their precipitation outlook calls for a better than even chance for above average precipitation during the next three months across the southern tier of states running from Arizona to the Southeastern Atlantic Coast, while chances of below average precipitation were better than even for this time span across most of the Northwest, centered upon western Oregon and northwestern California. The remainder of the contiguous states were given essentially equal chances of below and above average precipitation for October through December, 2014.
  A summary of the prognostic discussion of the 3-month outlook for non-technical users is available from CPC. These forecasts were based in part that assuming that an El Niño event had nearly a 65 percent of forming during the upcoming three months. A description is also provided as how to read these 3-class, 3-month Outlook maps.
- Seasonal Drought Outlook released -- The forecasters at NOAA's Climate Prediction Center also released their US Seasonal Drought Outlook last week that would run from late-September through December 2014. Their outlook would call for persistence of extensive drought conditions across western sections of the nation, primarily across a large section of the Pacific Coast (California and Oregon) along with Great Basin (Nevada and Utah) and the interior Northwest (including Washington and Idaho). Sections of the Southwest and the southern Plains, extending from southern California eastward to Texas and northward to Kansas could see some improvement in drought conditions during the rest of the year, including some areas that could removed from drought listings. The remainder of the nation does not appear to be headed for drought conditions. Note: a Seasonal Drought Outlook Discussion is included describing the forecasters' confidence.

CLIMATE AND THE BIOSPHERE

Warmer climate could signal later and longer fall foliage season -- Researchers at Princeton University claim that increased temperatures associated with climate change could result in a delay of the fall color season by as much as three weeks across the nation by the end of the 21st century. In addition, the length of this fall color season marked by changes in the colors of deciduous trees could increase. The higher temperatures of summer would linger into fall. The researchers used data collected on leaf-change dates for several tree species in both Alaska and Massachusetts and developed a model that can be used to predict the timing of the start of this season. [Princeton University News]
Coral growth rate on the Great Barrier Reef plunges over last four decades -- Researchers working on a Carnegie Institution expedition to Australia's Great Barrier Reef have discovered that coral growth rates on the reef have declined by approximately 40 percent since the mid-1970s. The scientists believe that ocean acidification may have played a significant role in the decline in the coral growth rate. [Carnegie Institution News]

CLIMATE AND SOCIETY

Remembering Hurricane Hugo after 25 years -- The National Weather Service Forecast Office in Charleston, SC recently created a website with video series and an interactive map that commemorates the 25th anniversary of the landfall of Hurricane Hugo, a massive category 4 hurricane (on the Saffir-Simpson Scale). At the time, Hugo was the strongest hurricane to strike the United States in more than 20 years and it also was the the nation's costliest hurricane on record, with an estimated $7 billion in damage. As many as 26 deaths were attributed to Hugo in the US, Puerto Rico and the US Virgin Islands. [NOAA Weather-Ready Nation News]
Earthweek -- Diary of the Planet [earthweek.com] Requires Adobe Acrobat Reader.

Concept of the Week: Climate and Architecture

Humans have been constructing houses and other buildings for thousands of years not only to protect themselves from the weather and other environmental factors, but also to create a comfortable indoor environment that would exhibit energy efficiency, especially in harsh climates. For centuries, natural or primitive housing reflected an adaptation to the climate of the locale and the availability of local building materials.

In order to maintain a tolerable level of comfort within a building, attention must be paid to thermal effects, ventilation, illumination and atmospheric humidity.

The indoor thermal state ultimately depends upon the building's energy budget involving incoming and outgoing radiation, latent and sensible heat loss and by interior heat sources or sinks. The indoor thermal level is mainly associated with the external energy load on the building. The external energy load on the building depends upon the latitude of the building, season of the year and time of day.

In tropical latitudes and during midday hours in summer, the sun's path across the local sky increases the solar radiation incident upon the roof and walls of the building. In polar latitudes, or during the winter or the amount of available sunlight is significantly lower, with the loss of infrared radiation causing a net cooling from the building. Changes in the color of the roof and the outer walls can affect the amount of incoming sunlight absorbed. Building orientation and the effective use of overhangs can also affect the amount of sunlight absorbed. Furthermore, the amount of insulation, often related to the thickness of the walls, reduces the conduction of heat into or out of the building. Thick adobe walls have been used effectively in the Southwest to moderate indoor temperature. These walls reduce the heat flow into the building during the daytime and in summer and out from the building at night or during winter.

The size and placement of windows also affects the energy balance. Large windows on the side of the building facing the sun's path tend to permit large amounts of sunlight to penetrate into the building. However, large windows on the side facing away from the sun can cause for heat loss due to conduction, as many types of windowpanes are not energy efficient.

Effective landscaping can reduce energy demands upon a dwelling: Deciduous trees planted on the south and west sides of the home provide cooling shade during the summer, keeping sunlight from entering the windows. These trees will lose their foliage in fall and allow the sun to shine through in winter, and warm south facing rooms. Evergreen trees or dense shrubbery on the north side can serve as a windbreak, which reduce the cold northerly winds from striking the house in winter.

Energy losses from buildings during the upcoming winter in northern latitudes can be seen readily by how quickly snow melts from roofs and by how big the icicles form. Heat losses from buildings occur with larger negative energy budgets, which are reflected also in higher heating bills during the winter season. However, the heating bills also depend upon the severity of the winter season that can be ascertained from the number of accumulated heating degree-day units. Check this week's Supplemental Information...In Greater Depth for how you can monitor the number of heating degree-day units to date in your state for this coming heating season.

Concept of the Week: Questions

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

The thicker the outdoor walls, the [(greater),(less)] the heat flow into or out of a building.
Planting [(evergreen),(deciduous)] vegetation on the south side of a home in New England will help reduce winter heating and summer cooling bills.

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. (24th-30th) On the 26th, 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)
27-28 September 1953...The strongest wind gust ever recorded during a hurricane was 175 mph at Chetumal, Mexico. (The Weather Doctor)
28 September 1893...Albuquerque, NM was soaked with 2.25 inches of rain, enough to establish a 24-hour record for that city. (The Weather Channel)
28 September 1986...Torrential rains and floods were responsible for South Africa's worst natural disaster in Natal. As much as 35 in. of rain fell between the 25^th and 29^th to the northeast of Empangen, resulting in 317 deaths and 163 people missing. Topsoil from some farms was completely washed away leaving only bedrock. (Accord Weather Calendar)

Return to DataStreme ECS website