Global Warming Turns Tundra to Forest: Study

Posted- June 3, 2012

http://news.yahoo.com/global-warming-turns-tundra-forest-study-173252619--finance.html;_ylc=X3oDMTNsM3M2MTI0BF9TAzk3NDkwNzkyBGFjdANtYWlsX2NiBGN0A2EEaW50bAN1cwRsYW5nA2VuLVVTBHBrZwM1NTYyMDRlZC0xMDc0LTNlNWQtYjYxNS1hNDYwMDI1NzA4ZTUEc2VjA21pdF9zaGFyZQRzbGsDbWFpbAR0ZXN0Aw--;_ylv=3

This week I read an article on global warming.  It was about how a forest is forming in the Arctic tundra. Scientists predicted this would happen but not this fast.  These forest trees started out as little shrubs.    Scientists anticipated that these shrubs would eventually form into trees in over a couple centuries.  They were very wrong.  It only took thirty to forty years for them to grow from small shrubs into two meter tall trees.  Now you may be thinking to yourself, “Why is this a bad thing? Trees are good for the environment.”  Well, the growth of these trees is warming the Arctic tundra which is not good because the Arctic tundra is covered in ice.  The trees warm the area and will make the ice melt faster in these areas which is not good for the Earth.  All this is happening in a one hundred thousand square kilometer area between Finland and Siberia.  Scientists knew that the sample area was a warmer part of the Arctic tundra than others.  Since it is a warmer part, it is easier for plants to grow.   When the shrubs start to grow the plants spread and start to grow in other places.   I hope scientists can overcome this problem and find a solution to help our environment and prevent global warming from spreading faster.

Emma Harrison

 May 31, 2012

 7A Science

 Ms. M

Tsunamis

Tsunamis are very rare but can be deadly when they do occur.  Tsunamis are a natural disaster.  They happen when two different tectonic plates collide.  Many times this happens when an earthquake occurs underneath the ocean floor.  There is so much pressure between the two tectonic plates that the top plate flips up creating a massive wave.  The wave goes in all directions and is called a tsunami.  In this essay, I will explore three main things about this so called rare natural disaster.  The first topic I will explore what a tsunami is and how tsunamis happen.  Second, I will tell you what the effects of a tsunami are.  Lastly, I will talk about what is being done to save lives when a tsunami occurs.

Not many tsunamis happened during the twentieth century.  So many people may not have a very clear understanding of them.   That is why I am going to tell you what a tsunami is.   A tsunami is a series of big waves that are formed when a large amount of ocean water is suddenly displaced.  This happens when an earthquake, volcano, or landslide occurs on the ocean floor or even from a meteorite falling into the ocean.  Eighty percent of all tsunamis mainly occur in the Pacific Rim area due to the large number of different tectonic plates in this region.  When the water is displaced, it creates a wave that move in all directions at a very fast rate.  These wave trains can move as fast as a jet plane and can cross an ocean in a day or less.  The closer the waves get to shore the higher the waves become and the more damage it does.  In fact, you might not even notice a tsunami wave if you were in the middle of the ocean because it slows down after leaving the epicenter.

As I said previously, tsunamis are very dangerous.  Often there is no warning a tsunamis is headed your way.  The first sign of tsunamis to the naked eye happens about five minutes before the first wave hits shore.  You might notice the tide going out unexpectedly and farther than normal exposing the ocean floor.  If you see this happening at the beach, run for high ground.  The first wave that hits will be larger than normal but not necessarily the biggest.  In a tsunami there will be a series of waves that hit but they can be as far about as one hour.  Tsunamis push ocean water far inland with great force destroying everything in its path.  For example, cars, buildings, trees, bridges, and people are tossed about and pulled back to sea.  Many people drown when the tsunamis hits land, others die from injuries caused by being hit by debris, or disease from polluted water on land after a tsunami.   For example, in December 2004 over 200,000 people died in Indonesia, Thailand, Madagascar, Shi Lanka, India, and Africa due to the worst tsunamis every recorded.  It was caused by a 9.2 earthquake that occurred off the cost of Sumatra, Indonesia.

At that time, there was no warning system which is one of the reasons the 2004 tsunamis caused so many deaths.   Even with a warning system today, there is often no way to save the lives of people living in coastal areas near the epicenter of tsunamis.  However, tsunamis warning systems can help people who live farther away by alerting them in advance tsunamis is coming.   There are warning systems for this type of natural disaster in the Pacific Rim today.   Using sensors on the ocean floor, scientists can detect disturbances such as earthquakes or underwater volcanic eruptions that can cause tsunamis to occur.  The sensors send messages to buoys on the ocean surface.  The buoys transmits messages to satellite that are sent to Hawaii where they monitored.  Based on this data, scientists can predict a tsunami and when it might hit land.  There are many issues that interfere with a warning system.  For example, in the Pacific Rim over twenty countries must cooperate to make it successful.  They speak many different languages and some countries are more wealthy than others so they all need to work together to make the system effective.

In conclusion, although tsunamis are rare they are also very deadly.

 

bib-

http://beachsafe.org.au/tsunami/ema/pages/03_workings.html

http://www.pep.bc.ca/tsunamis/causes_2.htm

http://environment.nationalgeographic.com/environment/natural-disasters/tsunami-profile/

http://www.universetoday.com/39319/effects-of-tsunamis/