The Foundation's Give 2 Griffin Annual Fund (G2G) is slightly over half-way toward its goal of $32,500 which will enable the organization to purchase a laptop cart and 30 laptops for our students to utilize in their ELA class and for standardized testing. They also plan to purchase 52 iPad tubs to help us store, charge and transport iPads easily. Scanning the QR code will enable you to make a donation in any amount and either a one-time contribution or monthly. Additionally, you can select a Foundation program to donate towards - the G2G Annual Fund for the laptops and iPad tubs; the Outdoor Classroom Development or the Barbara Quarles Scholarship Fund. Donations are tax-exempt.
Unit 3 is titled Weather & Climate. To begin the journey into Earth, we have to travel through the Atmosphere. Earth's Atmosphere has 4 layers: Thermosphere, Mesosphere, Stratosphere, and Troposphere. Part of this standard is comparing and contrasting each layer. It is also important to understand air pressure, and the ozone layer.
Earth's atmospheric layers Troposphere The troposphere is the lowest layer of our atmosphere. Starting at ground level, it extends upward to about 10 km (6.2 miles or about 33,000 feet) above sea level. We humans live in the troposphere, and nearly all weather occurs in this lowest layer. Most clouds appear here, mainly because 99% of the water vapor in the atmosphere is found in the troposphere. Air pressure drops, and temperatures get colder, as you climb higher in the troposphere. Stratosphere The next layer up is called the stratosphere. The stratosphere extends from the top of the troposphere to about 50 km (31 miles) above the ground. The infamous ozone layer is found within the stratosphere. Ozone molecules in this layer absorb high-energy ultraviolet (UV) light from the Sun, converting the UV energy into heat. Unlike the troposphere, the stratosphere actually gets warmer the higher you go! That trend of rising temperatures with altitude means that air in the stratosphere lacks the turbulence and updrafts of the troposphere beneath. Commercial passenger jets fly in the lower stratosphere, partly because this less-turbulent layer provides a smoother ride. The jet stream flows near the border between the troposphere and the stratosphere. Mesosphere Above the stratosphere is the mesosphere. It extends upward to a height of about 85 km (53 miles) above our planet. Most meteors burn up in the mesosphere. Unlike the stratosphere, temperatures once again grow colder as you rise up through the mesosphere. The coldest temperatures in Earth's atmosphere, about -90° C (-130° F), are found near the top of this layer. The air in the mesosphere is far too thin to breathe; air pressure at the bottom of the layer is well below 1% of the pressure at sea level, and continues dropping as you go higher. Thermosphere The layer of very rare air above the mesosphere is called the thermosphere. High-energy X-rays and UV radiation from the Sun are absorbed in the thermosphere, raising its temperature to hundreds or at times thousands of degrees. However, the air in this layer is so thin that it would feel freezing cold to us! In many ways, the thermosphere is more like outer space than a part of the atmosphere. Many satellites actually orbit Earth within the thermosphere! Variations in the amount of energy coming from the Sun exert a powerful influence on both the height of the top of this layer and the temperature within it. Because of this, the top of the thermosphere can be found anywhere between 500 and 1,000 km (311 to 621 miles) above the ground. Temperatures in the upper thermosphere can range from about 500° C (932° F) to 2,000° C (3,632° F) or higher. The aurora, the Northern Lights and Southern Lights, occur in the thermosphere. Air Pressure Colder air has higher air pressure and will move into areas of lower air pressure which also produces wind. Around the Earth, there are several major atmospheric “bands” where high or low pressure predominates with a general pattern of high pressure air movement to lower pressure areas. The greater the difference in air pressure between any two places at the same altitude, the stronger the wind will be. The boundaries where these high and low pressure areas meet are called fronts, and these fronts are usually very active in producing precipitation. Weather forecasters track the movement of high and low pressure areas, because they affect the patterns of other weather variables such as temperature, cloudiness, and wind. |
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Photo used under Creative Commons from fabian.kron