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Earth - Weather

The Earth's Biosphere is a result of several factors:

Seasonal Changes
Carbon Cycle

Global Warming |A Photo Gallery


It can be argued that a delicate balance is present here on Earth providing the environment for life to flourish. When we compare the extreme environment on Venus - with its well over 200 degree days and nights - and the lack of seasonal changes on Mars as a result of a thinning atmosphere and cold temperatures, it is easy to see the importance of our own biosphere. Of all the factors involved with the preservation of life, nothing is more evident than the seasonal changes on Earth.

The seasons are a result of the Earth's tilt. Contrary to popular belief, the Earth is not a greater distance from the Sun during winter - actually the Earth is closer to the Sun during winter! The reason for colder days is the shorter length of the day. During the summer months, the days are long and the Sun heats up the Earth's surface more so than in winter. The Sun is also higher in the sky during the summer months - a low Sun during winter spreads out the heat of the Sun over the Earth's surface.

The Seasons (Northern Hemisphere):

  • Spring - March 21
  • Summer - June 21
  • Autumn - September 22
  • Winter - December 21

The Seasons (Southern Hemisphere):

  • Autumn - March 21
  • Winter - June 21
  • Spring - September 22
  • Summer - December 21

For those who do not live in a "four seasons" environment, Spring is typical of wind and rain, Summer brings hot weather and some rain (thunderstorms as well), Autumn indicates cooling and some rain, and Winter having the shortest days, cold weather, rain and snow.

Rain (the release of condensation within clouds) can be a year around event, with heavier rains in more tropical environments (because of rapid temperature changes and moist air due to oceanic breezes). Rain - also known as precipitation - during the winter can freeze so the resulting weather brings snow. During rapid temperature changes of summer, such higher elevation freezing can result in hail, or frozen rain.

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The tidal motions of our oceans are a result of the Moon's gravity influence. The result of the ocean's motions provide energy for two very important effects:
Movement of the hot and cold ocean currents a result of a moving ocean. El Nino is the effect of shifting temperature changes in the tropical regions of the ocean.

For those of us in California, the tide is an important event to predict as this can invariably affect the surf. The NOAA offers a Water Level Tidal Predictions website for more information. Your local weather station may also have tide charts - but only if you live near the coast.

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Our atmosphere is very unique. While our primitive atmosphere was probably closer to the methane variety like Titan's atmosphere in the past, greenhouses gases, liquid water and the presence of plant life have shaped our atmosphere to its breathable, life-sustaining present. The purpose of our atmosphere is twofold: filter out harmful solar radiation and various regions of the EM-Band, and keep in some Solar radiation to maintain the surface temperature.

The solar radiation also has a curious effect - clouds. Clouds are the close formation of water vapor. Rising and falling of air produces condensation resulting in cloud formations.

In addition to cloud formation, temperature variations also produce winds. The warm equatorial regions and a spinning Earth produce clearly defined bands of circulation.

Our atmosphere as a whole boasts eight layers (from sea level on up):

  1. Troposphere
  2. Tropopause
  3. Stratosphere
  4. Stratopause
  5. Mesosphere
  6. Mesopause
  7. Thermosphere
  8. Ionosphere (not really a layer, but important)
Instead of sharply delineated borders between our atmosphere and space, the thermosphere gradually diminishes until there are not enough particles in a cubic space to constitute a layer. Because of the gradual dispersion of particles, the temperature in this region can climb pretty high. The Tropopause can shift position due to seasonal changes, and marks the location of the Jet Streams - rivers of high winds energized by UV radiation. The Ozone Layer exists just above the Tropopause.

The Mesosphere marks the location of decreased Oxygen. Very high mountains can pierce the Mesosphere and hypoxia (lack of oxygen in humans) occurs. The Ionosphere is not really a layer, but a region of charged particles as a result of Solar Radiation. Radio waves bounce off this region. For a more detailed look at our atmosphere:

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The Carbon Cycle:

The process of a "breathable" atmosphere is a direct result of what is called the Carbon Cycle. Water exists as a liquid here on Earth because of the temperature - and the temperature is a result of greenhouse gases trapping Solar Radiation so the Earth is warm. The process of introducing greenhouse gases (gases that trap infrared Solar energy) like carbon come from Plate Tectonics, or the movement of the continental plates. This movement results in several unpleasant reactions - like earthquakes and volcanoes - but are required for carbon introduction. The image below best describes how this process works:

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Weather (finally):

Weather is the phenomenon related to the effects of condensation, wind, and Solar Radiation. Temperature changes and seasonal variations provide the environments for weather to occur. Overall, weather is somewhat predictable in that certain weather patterns occur only during specific seasons - like thunderstorms and tornadoes during the Summer in West and Northern Texas. There is quite a laundry list of phenomenon that is considered weather (from the National Weather Service):

Winter Storms
High Winds
Freezing Rain
High Surf
Freezing Fog
Rain (Precipitation)
Tropical Storms

The National Weather Service has a website that provides up to date weather information and real-time maps and radar. As far as local weather, its difficult to find a forecast website that is not loaded with adds and pop-up windows. The National Weather Service does has some local stations so its possible your region will be near one of these locations - and its pop-up free.

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Global Warming:

We are not caring for our planet. The balance of natures own introduction of greenhouse gases is being countered by our own introduction of greenhouse emissions from cars, factories, and chemicals.

We are doing three terrible things to our planet:

  • Adding to the level of greenhouse gases

  • Deforestation cannot process natures introduction of carbon much less the additional carbon released by humans

  • Using chemicals like CFC's to punch a hole in our Ozone

Plants cleans the carbon out of the air and produces oxygen. Less plant life means less of this photosynthesis - or producing oxygen from carbon through the Sun's energy. The Ozone layer protects us from the higher energy UV radiation (ultraviolet radiation). In addition to increased risk of skin cancer, UV exposure also increases risk of cataracts and Macular Degeneration (something I know about working with eyes). So what of the Ozone hole?

The Ozone Hole Over Antarctica - 1999 The Ozone Hole Over Antarctica - 2001

Also, notice the levels of Ozone in the surrounding regions using the color bar - compare 1999 to 2001 and you can see there is a great danger here.

To keep up with the progress of the Ozone Hole - visit NASA's Ozone Hole Watch.

Also, think of how a melting Antarctica can dramatically change the ocean temperature - using the ocean current image presented earlier, just imagine how that can change the global climate.

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The Earth's weather related photo gallery:

Contrails from Jet Aircraft Aleutian Clouds
Aurora Australialis from the Space Shuttle Ocean Chlorophyll
Cirrus Clouds - Best Views in Infrared The Coral Atolls
Full Globe with Hurricane Andrew Antarctica - The Ross Ice Shelf
Hurricane Andrew Lightning from Space
Phytoplankton Blooms Shipping Tracks
Statocumulus Clouds Tornados from Space
Vortex - Wind Circulation Example Wildfires from Space

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