Sunday, October 21, 2007

The Future Is Drying Up

Thanks to debbyski for posting this on clipmarks.
clipped from www.nytimes.com


Draining The 100-foot-high bathtub ring left by the dwindling waters of Lake Mead, behind Hoover Dam.

Scientists sometimes refer to the effect a hotter world will have on this country’s fresh water as the other water problem, because global warming more commonly evokes the specter of rising oceans submerging our great coastal cities. By comparison, the steady decrease in mountain snowpack — the loss of the deep accumulation of high-altitude winter snow that melts each spring to provide the American West with most of its water — seems to be a more modest worry. But not all researchers agree with this ranking of dangers
In the Southwest this past summer, the outlook was equally sobering. A catastrophic reduction in the flow of the Colorado River — which mostly consists of snowmelt from the Rocky Mountains — has always served as a kind of thought experiment for water engineers, a risk situation from the outer edge of their practical imaginations. Some 30 million people depend on that water.

Saturday, October 20, 2007

Brain Can Only Pay Attention for 40 Minutes

I've known for years that my attention span in my graduate math classes has an upper limit of 45 minutes (probably a little less since the lecture usually doesn't start exactly on time). In situations where I don't have to pay attention continuously, I know my attention drifts in and out much more frequently than every 40 minutes or so, but if I already pretty much know what's going on, it doesn't matter much. I think the findings reported in this clip are significant in situations in which very careful attention to every detail is very important -- trying to follow a math proof, airport security, ...
Psychologists are finding out that even when people try to focus on a task they tend to lose concentration within 40 minutes, and sometimes as little as 10 minutes. The studies are based on a new technique, called transcranial Doppler sonography, that uses ultrasound to monitor blood flow velocity in the brain. The technique could be turned into a warning system for workers who perform critical tasks -- such as pilots or air traffic controllers -- or even for drivers.

Distractions can break anyone's concentration, but new research shows what happens in your brain can, too.
The phenomenon is such that the more you look, the less you see
transcranial Doppler sonography (TDS). The device measures blood flow velocity in the brain
researchers saw a decrease in blood-flow velocity over time, and, therefore, a decrease in attention
Warm believes the study results can be helpful for the military, security workers, air traffic controllers and many others

Friday, October 19, 2007

Possible Solutions to Atlanta Water Crisis

This continues from the same article as the previous clip -- I thought it was important enough to do one clip on the problem and one on possible solutions.
clipped from www.adn.com
Former Gov. Roy Barnes, a Democrat who was defeated in 2002, told reporters this week that he had planned to offer grants to fix leaks that waste millions of gallons of water each year. He also said he planned to build three new state reservoirs in north and west Georgia to help insulate the state from a future water crisis

It seems the idea of building state reservoirs is gaining steam in the Legislature as Georgia's battle with the Corps over federal reservoirs heats up.

Lt. Gov. Casey Cagle said he favors building more regional reservoirs shared by multiple communities to harness the 50 trillion gallons of water that fall over Georgia each year.

start using more "purple water" - waste water that is partially treated and can be used for irrigation, fire fighting and uses other than drinking
all outdoor watering across was banned across the northern half of the state, restaurants were asked to serve water only at a customer's request
take shorter showers

Atlanta Running Out of Water

clipped from www.adn.com
exposed lake bed at West Bank Park on Lake Lanier in Buford, Ga.

No backup if Atlanta's faucets run dry
less than a 90-day supply of water
Georgia Gov. Sonny Perdue seems to be pinning his hopes on a two-pronged approach: urging water conservation and reducing water flowing out of federally controlled lakes
Perdue's office on Friday asked a Florida federal judge to force the Army Corps of Engineers to curb the amount of water draining from Georgia reservoirs into Alabama and Florida
More than a quarter of the Southeast is covered by an "exceptional" drought - the National Weather Service's worst drought category
most of Tennessee, Alabama and the northern half of Georgia, as well as parts of North and South Carolina, Kentucky and Virginia
Lake Lanier, a 38,000-acre north Georgia reservoir that supplies more than 3 million residents with water, is already less than three months from depletion

Wednesday, October 17, 2007

Hubble Photos of Nebula

These photos are so beautiful! There are many more at the Hubble Site.
clipped from hubblesite.org

The Helix Nebula: a Gaseous Envelope Expelled By a Dying Star

The Helix Nebula: a Gaseous Envelope Expelled By a Dying Star
clipped from hubblesite.org

Gas Pillars in the Eagle Nebula (M16): Pillars of Creation in a Star-Forming Region

Gas Pillars in the Eagle Nebula (M16): Pillars of Creation in a Star-Forming Region
clipped from hubblesite.org

Uncovering the Veil Nebula

Uncovering the Veil Nebula
clipped from hubblesite.org

Star-Birth Clouds in M16: Stellar "Eggs" Emerge from Molecular Cloud

Star-Birth Clouds in M16: Stellar Eggs Emerge from Molecular Cloud
clipped from hubblesite.org

The Cat's Eye Nebula: Dying Star Creates Fantasy-like Sculpture of Gas and Dust

The Cat's Eye Nebula: Dying Star Creates Fantasy-like Sculpture of Gas and Dust
clipped from hubblesite.org

The Colorful Demise of a Sun-like Star

The Colorful Demise of a Sun-like Star
clipped from hubblesite.org

Eagle Nebula (M16) Pillar Detail: Portion of Top

Eagle Nebula (M16) Pillar Detail: Portion of Top
clipped from hubblesite.org

A Perfect Storm of Turbulent Gases in the Omega/Swan Nebula (M17)

A Perfect Storm of Turbulent Gases in the Omega/Swan Nebula (M17)
clipped from hubblesite.org

Crab Nebula: a Dead Star Creates Celestial Havoc

Crab Nebula:  a Dead Star Creates Celestial Havoc
clipped from hubblesite.org

The Bubble Nebula (NGC 7635)

The Bubble Nebula (NGC 7635)
clipped from hubblesite.org

The Eskimo Nebula (NGC 2392)

The Eskimo Nebula (NGC 2392)
clipped from hubblesite.org

The Cygnus Loop Supernova Remnant

The Cygnus Loop Supernova Remnant
clipped from hubblesite.org

The Cat's Eye Nebula

The Cat's Eye Nebula
clipped from hubblesite.org

Edifice of Gas and Dust in the Cone Nebula

Edifice of Gas and Dust in the Cone Nebula
clipped from hubblesite.org

The Cone Nebula (NGC 2264)

The Cone Nebula (NGC 2264)
clipped from hubblesite.org

Gas Plume From a Newborn Star in the Orion Nebula

Gas Plume From a Newborn Star in the Orion Nebula
clipped from hubblesite.org

Comet-like Filaments Along the Inner Rim of the Helix Nebula's Gas Ring

Comet-like Filaments Along the Inner Rim of the Helix Nebula's Gas Ring
clipped from hubblesite.org

The Ring Nebula (M57)

The Ring Nebula (M57)
clipped from hubblesite.org

Supernova Remnant N 63A

Supernova Remnant N 63A
clipped from hubblesite.org

Comet-Like Knots Around a Dying Star in the Helix Nebula

Comet-Like Knots Around a Dying Star in the Helix Nebula
clipped from hubblesite.org

Rainbow Image of the Egg Nebula

Rainbow Image of the Egg Nebula
clipped from hubblesite.org

Veil Nebula - Segment #2

Veil Nebula - Segment #2