|
|
The Sun is the driving force of our weather and climate. Its diameter is about 865,000 miles or 109 Earths lined up side by side and is so large that it makes up 99.99 percent of the mass of our Solar System. Our star - the Sun - is the most common type of star in the universe and has existed for nearly 4.6 billion years.
The composition of the Sun is about 92 percent hydrogen (the lightest element in the universe) and almost 8 percent helium (the second lightest element). Using these elements, the Sun generates energy through a process called thermonuclear reaction. This energy is created when the Sun fuses together hydrogen atoms to make a heavier element called helium. This process not only creates new elements, but also releases an enormous amount of energy. |
|
|
Uneven heating of the planet also occurs because of the curvature of the Earth. The planet receives most of its energy near the equator where the Sun's rays are directly (or nearly directly) hitting the planet. As you move toward the poles, the Sun's energy becomes more diffused and spread out over a greater area. Ultimately, the equator receives more energy from the Sun than it can radiate back into space. There is a surplus of energy. At the poles, the planet radiates more energy out into space than it receives from the Sun. There is a deficit of energy in these regions. The ultimate purpose of weather is to transfer the surplus of energy and heat to the poles and bring colder air toward the equator and find equilibrium.
|
|
|
All free moving objects appear to be deflected to the right in the Northern Hemisphere (and to the left in the Southern Hemisphere) because of the rotation of the Earth. This apparent deflection is called the Coriolis effect. Think of it this way. If you wanted to through a football from Salt Lake City, Utah to Las Vegas, Nevada, you could not throw it from point A to point B. Why? Because as the football is moving toward Las Vegas, the Earth underneath is rotating. By the time the football gets to where Las Vegas was when threw the football, the city that never sleeps has moved off. Thus, if you want to throw a football from Salt Lake City to Las Vegas you would need to grow it ahead of the city in hopes that the football and Las Vegas meet up at the same time.
|
|
|
Besides a football, what else is considered a "free moving" object. Free moving objects include airplanes, ocean currents, clouds, wind, hurricanes, or anything else that is not attached to the earth's surface. So how does this influence the atmosphere? As winds flow from high to low pressure, it deflects to the right (in the Northern Hemisphere) because of the earth's rotation. This deflection is nonexistent at the equator and progressively gets stronger towards the poles. Because of this, hurricanes can only form 5-20 degrees north or south of the equator. Near the equator, the water is warm enough but the Coriolis effect is too weak to make the hurricane rotate. Beyond 20 degrees latitude, the Coriolis effect is strong enough, but the waters are too cold.
|
The first letter is always lower case and determines the moisture content within the air mass.
|