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February 20, 2008 – Scientists from four well-known institutions say the next major disease like HIV/AIDS or SARS could occur in any of a number of developing countries concentrated along the equator. They encourage increased surveillance to prevent the spread of a potential outbreak.

Using global databases and sophisticated computer models to analyze patterns of emerging diseases, the researchers — from the Consortium for Conservation Medicine (CCM) at Wildlife Trust, N.Y., the Institute of Zoology, London, U.K., Columbia University, N.Y., and the University of Georgia, Athens, Ga. — are able for the first time to plot, map and predict where the next pandemic might occur.

Funded through a Human and Social Dynamics Exploratory Research award from the National Science Foundation (NSF), Arlington, Va., the research represents a major breakthrough in understanding where and why pandemic diseases emerge and provides a key tool for preventing them in the future.

“This is an important area of research,” said Rita Teutonico, advisor for integrative activities in NSF’s Directorate for Social, Behavioral and Economic Sciences. “After years of debate, the scientific community is now able to offer a convincing, predictive tool to help policy professionals and resource managers better allocate global resources in the fight against emerging diseases.”

By analyzing global patterns in human population density, population changes, latitude, rainfall and wildlife biodiversity in correlation with patterns of emerging diseases, the researchers were able to show for the first time definitive proof that the number of emerging diseases is increasing.

They cite zoonoses — diseases that originate in animals — as the primary problem and conclude these are the most current and important threat to humans. The research shows “that the key threat to public health is where human population growth and wildlife diversity clash,” said Peter Daszak, executive director of the Consortium for Conservation Medicine at Wildlife Trust.

The scientists analyzed 335 incidents of previous disease emergence and were able to identify the regions where future diseases were most likely to occur. They plotted the results on a global, ” Emerging Disease Hotspots” map.

“Our hotspots map shows that the next new important zoonotic disease is likely to originate in the Tropics, a region rich in wildlife species and under increasing pressure from people,” Daszak said.

This is the first time researchers are able to provide a scientific prediction of where the next major disease like HIV or SARS could emerge. During the last three decades, researchers have spent billions of research dollars to deal with the seemingly random emergence of dozens of pandemics. None of their efforts to understand patterns of emergence were successful.

This new research, published in the February 21 edition of the leading scientific journal Nature, successfully examined over 50 years of disease emergence patterns using a specially designed computer database to pinpoint regions of the world that need more monitoring.

Source : http://www.nsf.gov/

Just as the oil industry is turning to increasingly-sophisticated mapping techniques to find new oil fields, the renewable-energy industry hopes maps will chart its future. 3TIER, a Seattle-based firm, announced today what it calls the first global map of wind-power resources.

This first map is free to the public; later, more detailed maps and number-crunching will be for sale to the industry. The idea: Better information on exactly where, when, and how strong the the wind blows will help promote wind power, especially in developing parts of the world which haven’t been charted as meticulously as the U.S. or Europe.

Mapping wind resources isn’t quite the same as petroleum’s seismic imaging: 3TIER didn’t discover any hidden North Dakotas ripe for the picking. But getting the right data on wind itself is at the crux of wind power’s development. Many wind farm developers test wind for one or two years at a potential site; those early-stage projects make up the bulk of any wind developer’s “pipeline”. 3TIER’s models aim to reveal wind resources over a decades-long time frame.

“The fuel may be free, but all the money in the world won’t buy you more of it,” says Kenneth Westrick, 3TIER’s founder and chief executive and an atmospheric scientist.

Wind power’s limitations came to the fore during last week’s Texas brownouts, caused by a sudden cold front that killed the wind.That puts a premium on siting for wind farms. By building sophisticated models of a given area’s wind potential at different times, and with a host of climactic variables, Mr. Westrick hopes to be able to give wind farm developers more bang for their buck (and make some of his own.)

Finding the most consistently windy spots during dry weather, for instance, can show sites that will still produce electricity even when local hydroelectric power is down. That would make the electricity produced by wind power more valuable to wind farm owners and the utlities that buy the juice.

His next challenge? Getting the models to anticipate how climate change itself can disrupt wind patterns.

Source : http://blogs.wsj.com/

The Reason for Seasons: Earth Motions

* Q. Why is there Day and Night? The Earth rotates on its axis once every 24 hours.

earth`s rotation leads to day and night

* Q. Why are there Seasons?

The Earth’s spin axis is tilted with respect to its orbital plane around the Sun.

the tilt of earth’s axis results in seasons

This tilt has several ramifications.

* For the Northern hemisphere, in the winter we look to the south to see the Sun. In the summer it goes more nearly overhead.

* Winter daylight hours are fewer and the intensity of sunlight is less.
Thus it is colder in the Northern Hemisphere winter even though we are actually a little closer to the sun.

the tilt of the earth’s axis causes the sun to travel different paths in the sky through the year

* Seasons are reversed in the Northern and Southern Hemispheres.

A little more detail:

The tilt of earth’s axis increases the # of summer daylight hours and decreases the # of winter daylight hours. In the image, it is summer in the northern hemisphere and the regions above the equator will remain in the sunlight for a longer time. The north pole is receiving 24 hours of daylight.
The tilt of earth’s axis alters the intensity of sunlight received during different seasons – it is increased during summer and decreased during winter. This occurs because the beam of sunlight, which carries the same amount of energy, is concentrated over a smaller area in the region tilted towards the sun (where it is summer), and is spread over a larger area in the opposite hemisphere (where it is winter).

*
Note:
We see different stars during different seasons as a consequence of the Earth’s orbital motion around the sun.

the earth’s orbital motion around the sun results in different stars visible over the year

It’s Just A Phase: Moon Motions

As the moon orbits around the earth, we see different moon phases depending on the positions of the earth, moon, and sun. In the diagram below, you are looking down on the north pole of the earth. You can see that the lit half of the moon always faces the sun, but as the moon orbits around the earth, our viewing angle of the lit half changes. The phase that we see when the moon is in a particlar position is shown in the box beside the moon’s orbit.
moon phases

* Q. What time does the Full Moon rise?
(a) Midnight, (b) Noon, (c) Sunset, (d) Any old time and this is a trick question

full moon rises at sunset

* Q. It takes the moon 27 days to make a trip around the Earth. Then why is it more than 29 days between full moons? It takes 27 days for the moon to orbit the Earth with respect to the stars. However, the Earth orbits around the sun as the moon orbits around the Earth, so the moon must travel through an extra distance to make one orbit with respect to the Sun. Thus it takes 29 days for the moon to reach the same position with respect to the Sun.

moon orbit

Source:http://www.ucolick.org