Global warming...

What is..?
Global warming is the increase in the average temperature of Earth's near-surface air and oceans since the mid-20th century and its projected continuation. Global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) between the start and the end of the 20th century. The Intergovernmental Panel on Climate Change (IPCC) concludes that most of the observed temperature increase since the middle of the 20th century was very likely caused by increasing concentrations of greenhouse gases resulting from human activity such as fossil fuel burning and deforestation. The IPCC also concludes that variations in natural phenomena such as solar radiation and volcanic eruptions had a small cooling effect after 1950. These basic conclusions have been endorsed by more than 40 scientific societies and academies of science,[B] including all of the national academies of science of the major industrialized countries.

What causes bring this problem?
An increase in global temperature will cause sea levels to rise and will change the amount and pattern of precipitation, probably including expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with continuing retreat of glaciers, permafrost and sea ice. Other likely effects include changes in the frequency and intensity of extreme weather events, species extinctions, and changes in agricultural yields. Warming and related changes will vary from region to region around the globe, though the nature of these regional variations is uncertain.

Political and public debate continues regarding global warming and what actions to take in response. The available options are mitigation to reduce further emissions; adaptation to reduce the damage caused by warming; and, more speculatively, geoengineering to reverse global warming. Most national governments have signed and ratified the Kyoto Protocol aimed at reducing greenhouse gas emissions.

In my opinion this issue is one of the most relevants in the world because his impact falls in all of us. This problem beging with the greenhouse gases, that provocate the heating of the planet by not leating go the UV out of the planet (The UV are not reflected back).

More of this information can be found in so many articles and the internet is a very good source for this topic.

Natural Disaster. (Hurricane Katrina)

Date of disaster: August 23, 2005.
Type of disaster: Hurricane.

Description of disaster:
Hurricane Katrina formed over the Bahamas on August 23, 2005 and crossed southern Florida as a moderate Category 1 hurricane, causing some deaths and flooding there before strengthening rapidly in the Gulf of Mexico. The storm weakened before making its second landfall as a Category 3 storm on the morning of Monday, August 29 in southeast Louisiana. It caused severe destruction along the Gulf coast from central Florida to Texas, much of it due to the storm surge. The most severe loss of life occurred in New Orleans, Louisiana, which flooded as the levee system catastrophically failed, in many cases hours after the storm had moved inland. Eventually 80% of the city and large tracts of neighboring parishes became flooded, and the floodwaters lingered for weeks. However, the worst property damage occurred in coastal areas, such as all Mississippi beachfront towns, which were flooded over 90% in hours, as boats and casino barges rammed buildings, pushing cars and houses inland, with waters reaching 6-12 miles (10-19 km) from the beach.

Visual of the disaster:
Aftermath:
Economic effects:
The economic effects of the storm were far-reaching. As of April 2006, the Bush Administration had sought $105 billion for repairs and reconstruction in the region, and this does not account for damage to the economy caused by potential interruption of the oil supply, destruction of the Gulf Coast's highway infrastructure, and exports of commodities such as grain. Katrina damaged or destroyed 30 oil platforms and caused the closure of nine refineries; the total shut-in oil production from the Gulf of Mexico in the six-month period following Katrina was approximately 24% of the annual production and the shut-in gas production for the same period was about 18%. The forestry industry in Mississippi was also affected, as 1.3 million acres (5,300 km²) of forest lands were destroyed. The total loss to the forestry industry from Katrina is calculated to rise to about $5 billion.

Environmental effects:
Katrina also had a profound impact on the environment. The storm surge caused substantial beach erosion, in some cases completely devastating coastal areas. In Dauphin Island, approximately 90 miles (150 km) to the east of the point where the hurricane made landfall, the sand that comprised the barrier island was transported across the island into the Mississippi Sound, pushing the island towards land. The storm surge and waves from Katrina also obliterated the Chandeleur Islands, which had been affected by Hurricane Ivan the previous year. The US Geological Survey has estimated 217 square miles (560 km2) of land was transformed to water by the hurricanes Katrina and Rita. The lands that were lost were breeding grounds for marine mammals, brown pelicans, turtles, and fish, as well as migratory species such as redhead ducks. Overall, about 20% of the local marshes were permanently overrun by water as a result of the storm.

Government response:
The United States Northern Command established Joint Task Force (JTF) Katrina based out of Camp Shelby, Mississippi, to act as the military's on-scene response on Sunday, August 28, with US Army Lieutenant General Russel L. Honoré as commander. Approximately 58,000 National Guard personnel were activated to deal with the storm's aftermath, with troops coming from all 50 states. The Department of Defense also activated volunteer members of the Civil Air Patrol.

Retirement:
Because of the large loss of life and property along the Gulf Coast, the name Katrina was officially retired on April 6, 2006 by the World Meteorological Organization at the request of the U.S. government. It was replaced by Katia on List III of the Atlantic hurricane naming lists, which will next be used in the 2011 Atlantic hurricane season.

Reconstruction:
Reconstruction of each section of the southern portion of Louisiana has been addressed in the Army Corps LACPR (Louisiana Coastal Protection and Restoration) Final Technical Report which identifies areas to not be rebuilt and areas buildings need to be elevated.

Advantages & Disadvantages of Computers...

There are advantages and disadvantages of using computers nowdays...

The advantages can be such as:

Files can easily be shared between users. Network users can communicate by email. Security is good - users cannot see other users' files unlike on stand-alone machines. A file server is easy to back up as all the data is stored in one place. A computer allows a person to manipulate data easily and quickly, create text documents, edit them, print them, manipulate images, print them, send text and images over the Internet, download information over the Internet, interact with other people easily from home, keep records of transactions, activities, plan trips, and generally do far more than a person without a computer. Computers are very useful to make everyday life a lot easier. You can check the weather, email, search items, buy things type papers and much much more. You can also play games and post blogs and other stuff. People use computers in many ways. Can be used in business, inventions and scanners.

Some uf the Disadvantages are:

The teenagers of today's society have changed dramatically due to the Computer. Nowadays, the majority of teenagers have a PC and it has played a key role in their lives. Teenagers need to be equipped with knowledge of computer technology, as most things in life require the use of computers. One disadvantage of owning a computer is the information that students can access from the Internet. The Internet has also made the youth of today quite lazy, especially in terms of their education. If a student needs to research information for school, they merely access a relevant site and download the information, rarely paying attention to what is written. Purchasing the network cabling and file servers can be expensive. If the file server breaks down the files on the file server become inaccessible. Viruses can spread to other computers throughout a computer network. There is a danger of hacking, particularly with wide area networks. Computers are very engaging on children as well as adults. Kids with access to software that is not age appropriate may be exposed to such negative influences as violence, strong language, and over-stimulation from fast-action graphics.