WEEKLY CLIMATE NEWS

DataStreme ECS WEEK SIX: 14-18 October 2013

ITEMS OF INTEREST

Viewing atmospheric circulation in three-dimensions -- Read this week's Supplemental Information.. In Greater Depth for information concerning the average circulation in the lower and upper troposphere.
Celebrate Earth Science Week 2013 -- The National Oceanic and Atmospheric Administration, including the National Weather Service, along with NASA, the US Geological Survey and several professional scientific organizations such as the American Geological Institute have recognized next week (13-19 October 2013) as Earth Science Week 2013 to help the public gain a better understanding and appreciation for the earth sciences and to encourage stewardship of the Earth. This year's theme for the 15th annual Earth Science Week is "Mapping Our World", designed to engage "young people and the public in learning how geoscientists, geographers, and other mapping professionals use maps to represent land formations, natural resource deposits, bodies of water, fault lines, volcanic activity, weather patterns, travel routes, parks, businesses, population distribution, our shared geologic heritage, and more." [American Geological Institute]
"ClimateChangeLive" distance learning adventure webinar scheduled for this week -- The second in a series of seven webinars will be available between 7:30 and 9:00 PM this coming Wednesday, 16 October 2013. The series of webinars is designed to raise awareness and understanding of climate change science and is aligned to national science education standards. The collection of science-based, climate education resources and programs have been gathered from at least 19 federal agency and NGO partners that include the US Forest Service, NOAA, the US Fish and Wildlife Service. The theme of this second webinar scheduled for this Wednesday is "What Can We Learn from Schoolyard Trees?" Check http://climatechangelive.org/ for registration details.

CLIMATE FORCING

Explaining why sea ice around Antarctic is expanding while in Arctic sea ice is shrinking -- A recently produced Earth Gauge fact sheet describes the reasons why the sea ice around the Antarctic continent has been expanding over the last several decades while the sea ice covering the Arctic Ocean has shrunk to record minimum extent. [Earth Gauge]
Slower spinning of Earth causes time problems -- As the rate of rotation of the Earth slows slightly by a few extra milliseconds per day during the last half century, accurate time-keeping instruments have to be readjusted to take into account the slight lengthening of the mean solar day. In addition to chronometers for time keeping, changes in the rotation rate affect GPS signals and other highly sophisticated devices. The slowdown of the Earth's spin rate is due to the Moon's gravitation and its affect upon the oceanic tides on Earth and upon the planet's interior. [The Sydney Morning Herald]
Compaction of Nile Delta sediments is as important as rising seas -- A scientist at the Smithsonian Institution's National Museum of Natural History and colleagues from Italy claim that their analysis of subsurface sediments along Egypt's Nile Delta shows that subsidence rates due to compaction of these sediments are approximately four times greater than the rate of sea-level rise. This subsidence could cause the Nile Delta to be submerged within approximately 130 years. [ AGI Earth Magazine]

CLIMATE AND SOCIETY

Number of US homes at risk from wildfires are on the rise -- A data and analytics company recently released a report that determined the number of homes at risk from wildfires in the western US jumped 62 percent in the past year as more properties were developed in fire-prone areas. As many as 1.2 million homes valued at more than $189 billion were considered to be at high to very high risk from wildfires in California and a dozen other Western states. [Boulder Daily Camera News]
More than 500 million people could face increased freshwater scarcity -- Scientists at Germany's Potsdam Institute for Climate Impact Research warn that more than 500 million people around the world could face increased scarcity in freshwater if global temperatures did not rise by more than 2 Celsius degrees above pre-industrial levels. However, a rise by 50 percent in this number could occur if greenhouse gas emission were not cut soon, leading to a 5 Celsius degree increase in temperature that would make almost all the land area ice-free. The stability of ecosystems is also in doubt. [Potsdam Institute for Climate Impact Research 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.

REPORT FROM THE FIELD -- Barbara Des Rault, a DataStreme LIT mentor from Massapequa on New York's Long Island, reported that the Island has been experiencing unusually dry conditions that started in late summer and continued into autumn, as confirmed by the US Drought Monitor. She has observed that the Middle Atlantic coast that includes Long Island has been under the influence of very strong high pressure systems that have discouraged precipitation. While the weather has been spectacular, they need the rain. Because of the lack of precipitation, the foliage in New York has appears to be reaching peak color somewhat earlier than average, with subsequent leaf drop. She learned that deciduous trees stressed by drought often will accelerate their annual leaf shedding process.

Concept of the Week: Tropospheric westerly winds, north and south

The theoretical existence of upper tropospheric jet stream winds were not confirmed until being encountered by World War II bomber pilots when heading west into strong headwinds at altitudes of approximately 30,000 feet (10,000 m). Wind speeds sometimes exceeded 170 mph causing their relatively slow, heavily laden aircraft to almost stand still. Subsequently, westerly jet stream winds were found to encircle the planet in midlatitudes of both hemispheres above regions of strong temperature contrasts.

The explanation for these winds involves atmospheric mass distributions and forces on a rotating planet. Air in tropical latitudes is warmed, rises and then flows poleward, both north and south. On a rotating planet, moving air is deflected by the Coriolis effect, to the right in the Northern Hemisphere (and left in the Southern). The greater the temperature differences between warm lower and cold higher latitudes, the stronger the air motions and the faster the jet streams. The vertical temperature patterns result in the highest wind speeds near the top of the troposphere.

So Northern Hemisphere air headed northward, deflected to the right ends up headed east, a "westerly wind." In the Southern Hemisphere, southward moving air, deflected left will also go east, as a westerly wind. These "rivers" of strong upper-level winds steer surface weather systems as they move generally eastward across midlatitudes. They also provide boosts for jet aircraft headed eastward with them, but need to be avoided for going west! Of course, the full story is complex as land (especially mountains) and water surfaces interact with the heating of the air and eddies form in the turbulent flows, so jet streams wander. And with them go the storms and the weather patterns that form our short-term climate.

Concept of the Week: Questions

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

The Northern Hemisphere jet stream winds would be directed such that cold air is [(to the left),(to the right),(directly ahead)] of their forward motion.
In the Southern Hemisphere, the jet stream winds to be directed generally toward the [(south), (east), (west)].

Historical Events:

15-17 October 2005...The summit of Mount Washington, NH, the highest peak in the Northeast received 34 inches of snow between Saturday and Monday. The 24-hour record for the most snowfall was broken when 25.5 inches of snow piles up between noon Sunday and noon Monday. (The Weather Doctor)
16 October 1913...The temperature in Downtown San Francisco soared to 101 degrees to equal their record for October. (The Weather Channel)
16 October 1988...The afternoon high temperature of 100 degrees at Red Bluff, CA was the latest such reading of record for so late in the autumn season. (The National Weather Summary) (Storm Data)
17-18 October 2005...Heavy rain fell on Las Vegas, NV over the two-day period, with a rainfall total of 1.42 inches, which broke the full month record for October set in 1992. (The Weather Doctor)
17-19 October 2007...According to NOAA's Storm Prediction Center, 87 tornadoes were reported in the United States on these three days -- a new record outbreak for the month. With the outbreak, the monthly total of confirmed tornado reached 105, the second highest for October, behind the 117 in October 2001 since records began in 1950. Over 300 reports of severe weather were filed on 18 October across the lower and mid-Mississippi Valleys. (The Weather Doctor)
18 October 1984...Heavy snow began falling late on the 17^th at Salt Lake City and when it ended, 18.4 inches fell, setting a new 24-hour snowfall record. (Intellicast)
20 October 2004...Rain at two stations in Nevada broke the state's previous 24-hour maximum precipitation record of 7.13 inches set previously at Mt. Rose Highway Station (31 January 1963). The new state record of 9.78 inches was established at Mt. Charleston, while Kyle Canyon also broke the old record with 8.75 inches. (Accord Weather Guide Calendar)

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