International News/Weather

July 01, 2008

100 Year Anniversary

_44778275_tunguska_spl_466 At 7:17am on 30 June 1908, an immense explosion tore through the forest of central Siberia.

Some 80 million trees were flattened over an area of 2,000 square km (800 square miles) near the Tunguska River.

The blast was 1,000 times more powerful than the atomic bombs dropped on Hiroshima and Nagasaki and generated a shock wave that knocked people to the ground 60km from the epicentre.

The cause was an asteroid or comet just a few tens of metres across which detonated 5-10km above the ground, 100 years ago today.

Eyewitnesses recalled a brilliant fireball resembling a "flying star" ploughing across the cloudless June sky at an oblique angle.

The plume of hot dust trailing the fireball gave rise to descriptions of a "pillar of fire", which was quickly replaced by a giant cloud of black smoke rising over the horizon.

"The sky split in two and fire appeared high and wide over the forest. The split in the sky grew larger, and the entire northern side was covered with fire," one local remembered.

"At that moment I became so hot that I couldn't bear it, as if my shirt was on fire… I wanted to tear off my shirt and throw it down, but then the sky slammed shut. A strong thump sounded, and I was thrown a few yards."

This eyewitness was lucky, but an elderly hunter who was much closer to the explosion died after being flung against a tree by the blast. That the airburst did not cause more casualties was in large part due to the remoteness of the area.

To read more of this article click here.

June 20, 2008

Ice Like Found On Mars

Dice-size crumbs of bright material have vanished from inside a trench where they were photographed by NASA's Phoenix Mars Lander four days ago, convincing scientists that the material was frozen water that vaporized after digging exposed it.

"It must be ice," said Phoenix Principal Investigator Peter Smith of the University of Arizona. "These little clumps completely disappearing over the course of a few days, that is perfect evidence that it's ice. There had been some question whether the bright material was salt. Salt can't do that."

The chunks were left at the bottom of a trench informally called "Dodo-Goldilocks" when Phoenix's Robotic Arm enlarged that trench on June 15.  Several chunks were gone when Phoenix looked at the trench four days later. 

Also digging in a different trench, the Robotic Arm connected with a hard surface that has scientists excited about the prospect of next uncovering an icy layer. 

Check out photos of the possible ice here.

May 08, 2008

Myanmar Cyclone Aftermath Update

_44625578_storm_ap_220_300_2This is a shot of Cyclone Nargis on Friday before it made landfall in Myanmar, formerly knows as Burma, in the southern part of Asia.   As of noon Thursday the death toll still stands above 20,000.  However there are reports that over tens of thousands of people are still missing and at least 1 million are homeless.  Some emergency officials estimate the death toll could rise to over 100,000 because of the lack of food and drinking water and the danger of disease in the delta region.

Myanmar_tmo_2008126

Take a look at the image to the right.  The top image is a satellite photo of the delta region of Myanmar on April 15, 2008.  The image below it was assembled from data taken from satellites and a satellite photo to determine where the flooding was still occurring in Myanmar about three days after the cyclone hit late last week.  The images are from NASA.  You can see that there is still quite a bit of water covering much of this part of Myanmar.  Yangon, knows as Rangoon in English, is a city of about 4 million people.  The city is now only flooded but surrounded by water.  For the full story on this image click here

The government in Myanmar is run by the military and does not have a good relationship with the United States and many other western countries.  It has been a challenge to get aid into the area but relief agencies continue to do what they can.  There was some talk of doing a food drop but the United States has dismissed this idea unless they have permission from the Myanmar government.  There is some aid making it's way into the country through the United Nations but many countries have had limited access to the victims of this natural disaster. 

A cyclone is the same thing as a hurricane.  There are different names of the storms in different parts of the world.  Image011_3Nargis was a strong Category Three storm with winds up to 130 MPH and gusts 140 to 150 MPH.  To compare, Katrina made landfall as a Category Three Hurricane and the low-lying land of southern Louisiana is similar to that of coastal Myanmar.  The storm surge devastated villages, towns, and cities that had little warning the storm was approaching. 

April 17, 2008

The Earth Hums It's Own Tune

Check out this article by Charles Q. Quoi published on LiveScience.com.  The earth is always humming...and we aren't really sure why.  But it's pretty cool! - First Alert Meteorologist Erin Jordan

Earth gives off a relentless hum of countless notes completely imperceptible to the human ear, like a giant, exceptionally quiet symphony, but the origin of this sound remains a mystery.

Now unexpected powerful tunes have been discovered in this hum. These new findings could shed light on the source of this enigma.

The planet emanates a constant rumble far below the limits of human hearing, even when the ground isn't shaking from an earthquake. (It does not cause the ringing in the ear linked with tinnitus.) This sound, first discovered a decade ago, is one that only scientific instruments — seismometers — can detect. Researchers call it Earth's hum.

Investigators suspect this murmur could originate from the churning ocean, or perhaps the roiling atmosphere. To find out more, scientists analyzed readings from an exceptionally quiet Earth-listening research station at the Black Forest Observatory in Germany, with supporting data from Japan and China.

Different types

In the past, the oscillations that researchers found made up this hum were "spheroidal" — they basically involved patches of rock moving up and down, albeit near undetectably.

Now oscillations have been discovered making up the hum that, oddly, are shaped roughly like rings. Imagine, if you will, rumbles that twist in circles in rock across the upper echelons of the planet, almost like dozens of lazy hurricanes.

Scientists had actually expected to find these kinds of oscillations, but these new ring-like waves are surprisingly about as powerful as the spheroidal ones are. The expectation was they would be relatively insignificant.

New thinking

This discovery should force researchers to significantly rethink what causes Earth's hum. While the spheroidal oscillations might be caused by forces squeezing down on the planet — say, pressure from ocean or atmospheric waves — the twisting ring-like phenomena might be caused by forces shearing across the world's surface, from the oceans, atmosphere or possibly even the sun.

Future investigations of this part of the hum will prove challenging, as "this is a very small signal that is hard to measure, and the excitation is probably due to multiple interactions in a complex system," said researcher Rudolf Widmer-Schnidrig, a geoscientist at the University of Stuttgart, Germany.

Still, a better understanding of this sound will shed light on how the land, sea and air all interact, he added.

Researcher Dieter Kurrle and Widmer-Schnidrig detailed their findings March 20 in the journal Geophysical Research Letters.

April 03, 2008

ICE SHELF COLLAPSE AS SEEN FROM SPACE

Wilkins_tmo_2008060Check out these photos...look closely at the center of the photos. This is the Wilkins Ice Shelf in Antarctica collapsing.  You can see how it starting to collapse on February 28th and the full collapse the next day.  The rest of the Wilkins Ice Shelf, about the size of Connecticut, is just barely hanging onto land.  It is in danger of collapse as well. However, as the southern Hemisphere heads into winter scientists are hoping the cooler weather will hold the ice shelf at least for one more year.  The information below is from NASA. - First Alert Meteorologist Erin Jordan

Ice shelves are thick slabs of ice that are attached to coastlines and extend out over the ocean. In the natural course of events, ice shelves often calve large icebergs. Beginning in the mid-1990s, however, some ice shelves began exhibiting a new behavior: rapid disintegration into small pieces, likely as the result of warming temperatures.

The disintegration of the Wilkins Ice Shelf was announced by the National Snow and Ice Data Center, the British Antarctic Survey, and the Earth Dynamic System Research Center at Taiwan’s National Cheng Kung. According to the institutions’ joint press release, an iceberg measuring 41 by 2.5 kilometers (25.5 by 1.5 miles) broke off from the Wilkins Ice Shelf on February 28, leading to uncontrolled disintegration. Separated by just under 16 hours, these MODIS images show the rapid rate of disintegration; the growing region of pale blue on the ice shelf is crumbling, water-saturated ice.

For more information on the collapse of the Wilkins Ice Shelf and the continued loss of other ice shelves check out NASA's Earth Observatory

March 28, 2008

EARTH HOUR

Earth Hour takes place from 8 to 9 PM on Saturday.  It's an hour when cities, buildings, homeowners, etc, turn off all unnecessary lights.  The idea is to raise awareness that even one person can make a difference.  By turning off unnecessary lights we can see how much energy we are wasting.  Also in southern Arizona it brings the issue of light pollution to the forefront.  Reducing light pollution is a good thing since a good portion of our economy has to do with astronomy.  Phoenix is participating.  Check out the details about Earth Hour by clicking here

March 21, 2008

Why is Easter So Early?

Easter is always the first Sunday after the first full moon after the Spring Equinox which occurred at 10:48 PM on Wednesday night.  The full moon occurs at 11:39 AM this Friday morning. 

This dating of Easter is based on the lunar calendar that Hebrew people used to identify Passover, which is why it moves around on our Roman calendar. This year, Easter falls on March 23.

Based on the above, Easter can actually be one day earlier (March 22) but that is pretty rare. This year is the earliest Easter any of us will ever see the rest of our lives, and only the most elderly of our population (95 years old or above) have ever seen it this early before. None of us have ever, or will ever, see it a day earlier.

The next time Easter will be this early (March 23) will be the year 2228 (220 years from now). The last time it was this early was 1913 (so if you're 95 or older, you are the only ones that were around for that).

The next time it will be a day earlier, March 22, will be in the year 2285 (277 years from now). The last time it was on March 22 was 1818.  So, no one alive today has or will ever see it any earlier than this year.

March 18, 2008

Spring Begins Wednesday Night For Arizona

You may notice your calender saying that spring begins on the Thursday, March 20th.  Technically it does, but not here in Arizona.  We measure all time across the world from the Prime Meridian, which is 0 degrees longitutude. This line runs through Greenwhich, England, which we use as the offical base for our world time.  We refer to time zones as plus or minus hours and half-hours from the time in Greenwhich.  The vernal equinox, the official beginning of spring in the northern Hemisphere (versus fall in the southern hemisphere), occurs at 5:48 AM Greenwhich Mean Time or GMT.  GMT is also referred to as Universal Coordinated Time (UTC) or Zulu (a military term).  Arizona is 7 hours behind GMT.  That means spring begins at 10:48 PM on Wednesday for our area. - First Alert Meteorologist Erin Jordan

Cold Winter Across the World

From the National Oceanic & Atmospherice Administration

NOAA: Coolest December-February Since 2001 for U.S., Globe

The average temperature across both the contiguous U.S. and the globe during December 2007-February 2008 (climatological boreal winter) was the coolest since 2001, according to scientists at NOAA's National Climatic Data Center in Asheville, N.C. In terms of winter precipitation, Pacific storms bringing heavy precipitation to large parts of the West produced high snowpack that will provide welcome runoff this spring.

U.S. Winter Temperature Highlights

In the contiguous United States, the average winter temperature was 33.2°F (0.6°C), which was 0.2°F (0.1°C) above the 20th century average - yet still ranks as the coolest since 2001. It was the 54th coolest winter since national records began in 1895.

Winter temperatures were warmer than average from Texas to the Southeast and along the Eastern Seaboard, while cooler-than-average temperatures stretched from much of the upper Midwest to the West Coast.

With higher-than-average temperatures in the Northeast and South, the contiguous U.S. winter temperature-related energy demand was approximately 1.7 percent lower than average, based on NOAA's Residential Energy Demand Temperature Index

U.S. Winter Precipitation Highlights

Winter precipitation was much above average from the Midwest to parts of the West, notably Kansas, Colorado and Utah. Although moderate-to-strong La Niña conditions were present in the equatorial Pacific the winter was unique for the above average rain and snowfall in the Southwest, where La Niña typically brings drier-than-average conditions.

During January alone, 170 inches of snow fell at the Alta ski area near Salt Lake City, Utah, more than twice the normal amount for the month, eclipsing the previous record of 168 inches that fell in 1967. At the end of February, seasonal precipitation for the 2008 Water Year, which began on October 1, 2007, was well above average over much of the West.

Mountain snowpack exceeded 150 percent of average in large parts of Colorado, New Mexico, Arizona, and Oregon at the end of February. Spring run-off from the above average snowpack in the West is expected to be beneficial in drought plagued areas.

Record February precipitation in the Northeast helped make the winter the fifth wettest on record for the region. New York had its wettest winter, while Pennsylvania, Connecticut, Vermont, and Colorado to the West, had their second wettest.

Snowfall was above normal in northern New England, where some locations posted all-time record winter snow totals. Concord, N.Y., received 100.1 inches, which was 22.1 inches above the previous record set during the winter of 1886-87. Burlington, VT., received 103.2 inches, which was 6.3 inches above the previous record set during the winter of 1970-71.

While some areas of the Southeast were wetter than average during the winter, overall precipitation for the region was near average. At the end of February, two-thirds of the Southeast remained in some stage of drought, with more than 25 percent in extreme-to- exceptional drought.

Drought conditions intensified in Texas with areas experiencing drought almost doubling from 25 percent at the end of January to 45 percent at the end of February.

Global Highlights

The combined global land and ocean surface temperature was the 16th warmest on record for the December 2007-February 2008 period (0.58°F/0.32°C above the 20th century mean of 53.8°F/12.1°C). The presence of a moderate-to-strong La Niña contributed to a boreal winter and February temperature that were the coolest since the La Niña episode of 2000-2001.

While analyses of the causes of the severe winter storms in southern China continues, NOAA Earth System Research Laboratory scientists are focusing on the presence of unusually strong, persistent high pressure over Eastern Europe, combined with low pressure over Southwest Asia. This pattern directed a series of storms across the region, while northerly low level flow introduced cold air from Mongolia. Unusually high water temperatures in the China Sea may have triggered available moisture that enhanced the severity of these storms.

Record Northern Hemisphere snow cover extent in January was followed by above average snow cover for the month of February. Unusually high temperatures across much of the mid- and high-latitude areas of the Northern Hemisphere in February began reducing the snow cover, and by the end of February, snow cover extent was below average in many parts of the hemisphere.

While there has been little trend in snow cover extent during the winter season since records began in the late 1960s, spring snow cover extent has been sharply lower in the past two decades as global temperatures have increased.

February 29, 2008

Saguaro National Park Turns 75 on Saturday!

Lots of great events are going on at Saguaro East and West on Saturday to celebrate this milestone birthday.  Admission is free!  Get out and celebrate this national treasure that spotlights our unique southern Arizona ecology. - First Alert Meteorologist Erin Jordan

Saguaro National Park West

9 AM Footprings on the Landscape

10 AM Formal 75th Anniversary presentations

12:15 PM Homesteading Adventures in the Desert

1:15 PM The CCC and its impact on Saguaro National Park

2:15 PM Masters of Microscopes, 75 years to Decode the Desert

3 PM Mountain Lions and Boblcast in the Tucson Mountains

4 PM They're Mining in Our National Park?

Saguaro National Park East

9 AM Tea with Homer and Viola

10 AM 1933 to Today, Saguaro National Park

10 AM Meet the Saguaro

10 AM Children's Corner, Arts and Crafts

10:30 Signs of Life

11 AM Little House on the Desert Hike

12 PM 75 Years at Saguaro National Park, An Illustrated History

1 PM History fo the Rincon Mountains

1:30 PM The Giant Saguaro, Yesterday, Today, and Tomorrow

2 PM The Changing Cactus Forest

3 PM Saguaro Nation Park, the Next 75 Years

On March 1st, 1933 President Herbert Hoover signed a proclamation creating Saguaro National Monument.  It became a National Park in 1994.  There are 91,440 of pristine desert in the two districts east and west. The eastern portion is at the base of the Rincon Mountains. The western portion is in the Tucson Mountains.  At 10 AM at the Red Hills Vistors Center in Saguaro National Park West there will be an offical celebration.  Scheduled to speak at this event area Dorothy Bush Koch (the President's sister), Tricia Reilly Koch, Congressman Raul Grijalva, Kristin Almquist (Director of the Governor's Southern  Arizona Office), and Lindi Harvey (Deputy Director of the National Park Service).  The Tucson Girls Chorus will also perform. 

Red Hills Visitor Center, Saguaro West 520.733.5158

Rincon Mountain Vistor Center, Saguaro East 520.733.5153