Tuesday, March 29, 2011

ALL YOU NEED TO KNOW ABOUT TSUNAMI'S...

What are tsunamis?
Tsunamis are large ocean waves generated by major earthquakes beneath the ocean floor or major landslides into the ocean. Tsunamis caused by nearby earthquakes may reach the coast within minutes. When the waves enter shallow water, they may rise to several feet or, in rare cases, tens of feet, striking the coast with devastating force. People on the beach or in low coastal areas need to be aware that a tsunami could arrive within minutes after a severe earthquake.
The tsunami danger period can continue for many hours after a major earthquake. Tsunamis also may be generated by very large earthquakes far away in other areas of the ocean. Waves caused by these earthquakes travel at hundreds of miles per hour, reaching the coast several hours after the earthquake. The International Tsunami Warning System monitors ocean waves after any Pacific earthquake with a magnitude greater than 6.5. If waves are detected, warnings are issued to local authorities who can order the evacuation of low-lying areas if necessary.
                             Why prepare for tsunamis?
All tsunamis are potentially, if rarely, dangerous. Twenty-four tsunamis have caused damage in the United States and its territories in the past 200 years. Since 1946, six tsunamis have killed more than 350 people and caused significant property damage in Hawaii, Alaska, and along the West Coast. Tsunamis have also occurred in Puerto Rico and the Virgin Islands.

When a tsunami comes ashore, it can cause great loss of life and property damage. Tsunamis can travel upstream in coastal estuaries and rivers, with damaging waves extending farther inland than the immediate coast. A tsunami can occur during any season of the year and at any time, day or night.

How can I protect myself from a tsunami?

If you are in a coastal community and feel the shaking of a strong earthquake, you may have only minutes until a tsunami arrives. Do not wait for an official warning. Instead, let the strong shaking be your warning, and, after protecting yourself from falling objects, quickly move away from the water and to higher ground. If the surrounding area is flat, move inland. Once away from the water, listen to a local radio or television station or NOAA Weather Radio for information from the Tsunami Warning Centers about further action you should take.

Even if you do not feel shaking, if you learn that an area has experienced a large earthquake that could send a tsunami in your direction, listen to a local radio or television station or NOAA Weather Radio for information from the Tsunami Warning Centers about action you should take. Depending on the location of the earthquake, you may have a number of hours in which to take appropriate action.

What is the best source of information in a tsunami situation?

As part of an international cooperative effort to save lives and protect property, the National Oceanic and Atmospheric Administration’s National Weather Service operates two tsunami warning centers: the West Coast/Alaska Tsunami Warning Center (WC/ATWC) in Palmer, Alaska, and the Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii. The WC/ATWC serves as the regional Tsunami Warning Center for Alaska, British Columbia, Washington, Oregon, and California. The PTWC serves as the regional Tsunami Warning Center for Hawaii and as a national/international warning center for tsunamis that pose a Pacific-wide threat.
Some areas, such as Hawaii, have Civil Defense Sirens. Turn on your radio or television to any station when the siren is sounded and listen for emergency information and instructions. Maps of tsunami-inundation areas and evacuation routes can be found in the front of local telephone books in the Disaster Preparedness Info section.

Tsunami warnings are broadcast on local radio and television stations and on NOAA Weather Radio. NOAA Weather Radio is the prime alerting and critical information delivery system of the National Weather Service (NWS). NOAA Weather Radio broadcasts warnings, watches, forecasts, and other hazard information 24 hours a day on more than 650 stations in the 50 states, adjacent coastal waters, Puerto Rico, the U.S. Virgin Islands, and the U.S. Pacific territories.

The NWS encourages people to buy a weather radio equipped with the Specific Area Message Encoder (SAME) feature. This feature automatically alerts you when important information is issued about tsunamis or weather-related hazards for your area. Information on NOAA Weather Radio is available from your local NWS office or online.
Carry the radio with you when you go to the beach and keep fresh batteries in it.



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Friday, March 11, 2011

LOGGERHEAD SEA TURTLE

Physical Appearance
The amazing Atlantic loggerhead sea turtle (Caretta caretta) can have a shell as long as 2.7 m (9 ft) and weigh 454 kg (1,000 lbs.)!! However, on average the loggerhead turtle is 90 cm (3 ft) long and 136 kg (300lbs) in weight.Loggerheads have large heads because they have large jaw closing muscles, allowing them to have an extremely powerful and crushing bite. They are reddish-brown in colour with olive and yellow colour tinges on their body and shell.

Feeding Habits
These sea turtles are mainly carnivores and eat sponges, jellyfish, mussels, clams, oysters, shrimp, and horseshoe crabs. It is the powerful jaws of loggerheads that allow them to easily crush the hard shells of their prey. Loggerheads can actually come in contact with the deadly tentacles of the Portuguese-man-of-war and remain unharmed!

Current Status and Threats
Atlantic loggerhead turtles are considered threatened in the United States. The largest population, of about 15,0000 loggerhead turtles, is in the Greater Antilles and the eastern United States. However, the Carolinas record a three percent decrease in the occurrence of C. caretta each year. Here are some reasons for their declining populations:

Habitat Loss due to human coastal development is one of the main reasons for their declining numbers. In fact, the nesting habitat of all species of sea turtles is disturbed or destroyed by humans.
Pollution from human garbage and effluents can have devastating effects on sea turtles. Garbage, such as plastics bags, can be mistaken by a sea turtle for a jellyfish and eating plastic is deadly because it can suffocate the turtles or the plastic can get stuck in their digestive tract.

Accidental Capture in Shrimp Trawls and Fishing Lines
Nest Robbing by humans and predators, such as raccoons, make the life of a sea turtle difficult before they are even born.
Artificial Light on coasts from cities cause disorientation of nesting females and hatchlings trying to find their way to the sea.

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