Cells to Systems

http://www.livebinders.com/play/play?id=46976

Cells Are So Clever

Earth day 2013 The Face of Climate Change

The Face of Climate Change

Climate change can seem like a remote problem for our leaders, but the fact is that it's already impacting real people, animals, and beloved places. These Faces of Climate Change are multiplying every day.

What A Wonderful World With David Attenborough -- BBC One [FULL HD]

What causes the seasons?

What causes the seasons?
The seasons are caused by the tilt of the Earth's rotational axis away or toward the sun as it travels through its year-long path around the sun. The Earth has a tilt of 23.5 degrees relative to the "ecliptic plane" (the imaginary surface formed by it's almost-cicular path around the sun). The tilt toward the sun is maximized during Northern Hemisphere summer in late June (the "summer solstice"). At this time, the amount of sunlight reaching the Northern Hemisphere is at a maximum. In late December, on the date of the "winter solstice", the Earth's tilt away from the sun is maximized, leading to a minimum of sunlight reaching the Northern Hemisphere. The seasons, of course, are reversed in the Southern Hemisphere. During the winter, cold air masses build up over North America, Europe, and Asia, due to the low intensity of sunlight. The oceanic air masses are much less affected by the seasons because circulations in the upper ocean replenish warm surface water if it has been cooled. The strong temperature contrast between the cold air masses over land and the relatively warmer air masses over the ocean lead to extratropical (non-tropical) cyclone formation (low pressure). These storms are thus much more frequent and intense in the winter than in the summer.
Interesting facts:
The sun is actually closest to the Earth during Northern Hemisphere winter (not summer). Thus, the amount of sunlight averaged over the whole Earth, is as much as 7% more intense in the winter than the summer. Despite this fact, the global-average surface temperature is warmer in Northern Hemisphere summer, due to the much greater expanse of land there, and since land heats to a higher temperature than the ocean does.
http://www.weatherquestions.com/What_causes_the_seasons.htm

What Causes Earth's Seasons?

The Water Cycle

  We are going to explain about the water cycle: evaporation, transpiration, condensation, precipitation, runoff and collection.

    Evaporation is when the sun heats up the water in rivers, lakes or the oceans. It transforms into steam or vapor. The steam or vapor goes in to the air. Transpiration is when the plants give off a little bit of water vapor.

 Water vapor in the air gets very cold and changes back in to liquid. The water vapor condenses and forms clouds.

 Precipitation occurs when there is a lot of water condensed, and the clouds are full of water and can’t hold any more the water. The clouds get heavy and it can rain or snow.

 Runoff is the movement of land water to the oceans mainly in the forms of rivers, lakes and streams.

 Collection is when the water falls back to earth as precipitation, it may fall back in the oceans, lakes or rivers or it may end up on land. When it ends up on land, it will either soak into the earth as ground water or it may run over the soil and collect in rivers, lakes or oceans.

Water is in a constantly moving cycle and heat is the key to how this happens. Water changes its form as it is heated or cooled. When it is heated it turns to steam or vapor and when it is cooled it turns back to a liquid or into solid ice.

We study allot to write this text.  We hope you enjoy our presentation!

Daniel,Juliana,Catarina,Paul