Saturday, September 27, 2008

Hurricanes




Also known as tropical cyclones, a hurricane is a very powerful force of spinning air that can cause so much damage to both property and life. It is of the element air. It is a storm system that is identified by a low pressure center and thunderstorms around the edge that create strong winds and heavy rain that causes flooding.
They are called tropical cyclones because they form almost only in tropical climates. When moist air rises it creates heat that the cyclone feeds on. This results in the condensation of water vapour that is contained in the moist air. Their energy is of a different heat mechanism to that of other cyclonic winstorms like the European windstroms hence their classification as the "warm core" strom systems.
In the Nortern hemisphere a cyclone rotates anti-clockwise and in the Southern hemisphere it rotates clockwise. They are called different names depending on their strength and location e.g. hurricane od typhoon.
As well as producing heavy rain, strong winds, high waves and strom surges they are also capable of producing tornadoes. They start over big bodies of warm water and they lose their energy and strngth if they travel over land. Although they don't travel too far inland, the rain that falls from them and the strom surges caused by them can cause flooding up to 40 kilometres from the coast.
Although they can cause devastating effects on human population they can also relvieve droughts. And although they only start in tropical areas they can travel to temperate latitudes which plays an important role on the global atmospheric circulation mechanism!
They can be devastating but they help maintain equilibrium in the Earth's troposphere and they also maintain a relatively warm and stable temperature worldwide.

Monday, September 22, 2008

Wildfires


Forest fires are another another natural occurance of the element fire! They occur in wildland areas and are uncontrolled. But they often spread and destroy agricultural resources and housing. They are commonly started by lighting, careless human activity, volcanic eruptions and arson. Droughts and heat waves can severly increase the chances of wildfires occuring.
In modern times it is accepted that they are a natural occurance of the ecosystem. Some plants have even evolved to survive fires, thanks to wildfires. Also the germinataion of seeds are stimulated by smoke, heat and charred wood, all components of wildfires.
But alot of ecosystems are suffering from too much forest fires!

I got this image from www.lpi.usra.edu/.../wildfiresweb.html

Friday, September 19, 2008

Earthquakes


I am writing about earthquakes as part of the element earth. Earthquakes occur when there is a sudden release of energy from the earth's crust. This energy creates seismic waves. Earthquakes are recorded using a seismograph. The Richter scale measures the amount of seismic activity, above 7 causing serious damage and below 3 being imperceptible. The Mercalli scale measures the intensity of shaking. When the epicentre of a big earthquake occurs off-shore then there might be enough movement on the seabed to cause a Tsunami.

I got this image from www.scienceclarified.com/Di-El/Earthquake.html

Monday, September 15, 2008

Tornadoes


Tornadoes are of the element air! And so i am posting this post under the element air.
They come in many different sizes but they are all generally in the shape of a funnel, the narrow end of which is in contact with the the earth. The wide end is usally in contact with the base of a comulonimbus cloud and rarely with the base of a cumulus cloud! The end of the tornado that is in contact with the ground is usually surrounded with the debris that it has picked up.
Usually tornadoe's wind speeds are between 40 and 110mph and are about 75 meters across. They are able to travel a few miles before they break up. Some can reach wind speeds of up to 300mph and can be as wide as 1 mile and can travel for dozens of miles. The only continent that a tornado has not been seen on is Antarctica and most of them occur in America!

I got this image from http://www.uwm.edu/~kahl/Images/Weather/Severe/multiple_tornadoes.html

Friday, September 12, 2008

Thursday, September 11, 2008

Water-Tsunami


T-sunami's are a very powerful force. Capable of causing alot of destruction if they hit a populated area. The cost to repair the damage that a T-sunami does can be extremly high!
The picture above is of the Asian T-sunami in 2004. As you can see from the picture, the people didn't have time to get out of the way, they had no warning at all and were struck with with such a violent force. It caused mayhem as you can see, people were running all over the place to get out of the way!
T-sunami's are caused by earthquakes, both above and beneath the ocean, landslides, mass movements, nuclear testing and some volcanic eruptions!
Due to the immense volunes of water that T-sunamis carry the effects of them can be devastating.

I got this image from www.3mfuture.com/.../tsunami-alarm-system.htm

Monday, September 8, 2008

Sunday, September 7, 2008

Earth


Earth is a very powerful force. It isn't as flashy as fire or as quick air but it is big and strong. It is the home of two other elements; fire and water! It has huge looming mountain ranges, great oceans and vast dry deserts. The tectonic plates under the earth move and cause earthquakes and if they move under water they may cause Tsunami's! They also make volcanoes and cause them to erupt when they move. One of the biggest, violent and most destructive things caused by earth is earthquakes and it is what i will use to represent earth!

I got this image from profile.myspace.com/index.cfm?fuseaction=user...

Friday, September 5, 2008

Air


There is a layer of gases that create the earth's atmosphere and they are commonly known as air. Air provides us with oxygen to breath so we can survive on this planet. The air also absorbs some solar radiation to protect life on earth Wind causes surface movement and provides it with waves. Wind and air is a very powerful force when it reaches high speeds.Wind can cause tress to grow in certain ways and can also shape landforms. I personally think that it is the most powerful element but if you think otherwise please leave a comment or do my poll!

I got this image from www.eo.ucar.edu/kids/sky/air1.htm

Thursday, September 4, 2008

Firery Volcano


This is a picture of Kilauea, an Hawaiin volcano! It is the world's most active volcano. It is the youngest volcano on hawaii and only appears as a little bulge on the south eastern edge of Mauna Loa, another volcano on Hawaii. It has magma plumbing systems that reach 60km into the earth. Since 1952 it has had 34 eruptions and because of it's last eruption it got the title of world's most active volcano. And since 1983 it's eruptive activity has been continuous.
When the lava erupts from Kilauea it travels 11km down a tube system into the sea.
I am using volcanoes as a way to represent non-man made fires! The lava is so hot that it burns everything in it's path and sets it alight. Also i will use natural forest fires to represent fire. Fire is probably the flashiest element!

I got this image from gorp.away.com/.../us_national_park/hi_hawai.htm

Monday, September 1, 2008

Water


Water takes up roughly 70% of the earths surface as a liquid and as a solid. And it is also found in the atmosphere as water vapour! It is one of the few substances that can take on the three forms; liquid, sold and gas! When at room temperature it is almost colourless, tasteless and odourless. It is commonly refered to as the universal solvent due to it's ablilty to dissolve many substances in it.

I got this image from www.treehugger.com