predicting weather and climate change

weather technology

A scientist who uses weather causes to try and predict weather is known as a meteorologist. Meteorologists use maps, charts, and computers to try and predict the weather and prepare forecasts. So where do the meteorologists get their information? The National Weather Service! The National Weather Service uses: Satellites Weather Balloons Radars Instruments Weather Maps

Air Pressure at equator and poles

Air pressure is lower at the equator and higher at the poles.

Explain the relationship between the movement of air masses, high and low pressure systems, and frontal boundaries to storms (including thunderstorms, hurricanes, and tornadoes) and other weather conditions that may result.

An air mass is a large section of the lower troposphere that has the same weather throughout. Air masses can form over continents, icecaps or the ocean. Air masses are controlled by patterns of heating and cooling over large areas of the Earth's surface. Changes in air pressure readings indicate the passing of high and low pressure systems. Differences in air pressure cause Earth's winds and weather changes. Storms are natural disturbances in the atmosphere that involve air pressure, clouds, precipitation, and strong winds. The major types of storms are thunderstorms, hurricanes, tornadoes, and winter storms. Each type has its own characteristics and dangers. Tornadoes are violently whirling winds sometimes visible as a funnel-shaped cloud. They are produced by severe thunderstorms. Spiraling high winds and extremely low pressure are the unique features of tornadoes. Thunderstorms are known as electrical storms. A thunderstorm is characterized by the presence of lightning and thunder. They are produced rapidly when rising air causes cumulus clouds to build upward into a thunderhead. The cloud type associated with thunderstorms are cumulonimbus. Thunderstorms are usually accompanied by strong winds, heavy rain and sometimes snow, hail or no precipitation at all. Thunderstorms are brief, intense storms that affect a small area. Hurricanes are huge, rotating storms that form over the ocean near the equator. They produce very strong winds, heavy rains, and large, powerful waves and can cause severe flooding and damage from strong winds. Floods occur when an area is inundated with water. Weather related flooding is most often associated with hurricanes and thunderstorms. Winter storms are associated with quickly moving cold fronts and they can produce high winds, very low temperatures plus include blizzards, ice storms and large accumulations of snow.

weather maps

Computers can help create diagrams known as weather maps. Weather maps demonstrate a large area such as North America and show what weather is happening in a short amount of time. These maps can be produced by data from satellites, radar, or surface data.

Barometer

Instrument used to measure air pressure. When air pressure increases, the mercury moves up the tube.

barometer

Measures air pressure Remember: H= Fair weather, L= Stormy weather

rain guage

Measures the amount of precipitation

thermometer

Measures the temperature

anemometer

Measures the wind speed

weather service maps

On some weather maps you may see curved lines. These lines connect places where conditions are similar. These lines are known as Isobars. These lines join places on the map that have the same pressure. Another type of line you could see is the Isotherm. These lines join places with the same temperature.

limits on technology

Science has helped us predict weather far better than we have been able to in the past. Some technology can predict somewhat accurate weather up to a month ahead using solar radiation patterns. But even with this technology the atmosphere is still very unpredictable. Even a small change such as a shift in the wind can completely change a forecast.

wind vane

Shows the direction of the wind

weather satellites

Some satellites are designed to take pictures of clouds and storms from space and then beam the pictures back to data centers. The first weather satellite was launched in 1960, but all it could do was produce pictures of storms, clouds, and snow cover. Today's newer satellites can give data on temperature, humidity, solar radiation, and wind direction.

Predict weather conditions and patterns based on information obtained from: • Weather data collected from direct observations and measurement (wind speed and direction, air temperature, humidity and air pressure). • Weather maps, satellites and radar • Cloud shapes and types and associated elevation

The earth has a variety of climates, defined by average temperature, precipitation, humidity, air pressure, and wind, over time in a particular place. Weather forecasting is an attempt to make accurate predictions of future weather. The accuracy of weather prediction is improving as technology advances. A weather map is useful for making predictions. Weather maps usually show precipitation, wind direction, temperature, cloud cover, high or low pressure, cold and warm fronts, stationary and occluded fronts. Weather systems generally move from west to east across the USA. Long rang weather forecasting is more difficult than short-range weather predictions. Technologies such as computer, satellite images and radar enable forecasters to track movements of large-scale weather systems like air masses and fronts. Weather data collection results from using direct observations and measurements such as wind speed, wind direction, air temperature, humidity, and air pressure. Wind direction can be shown by flags or blowing dust. The actual wind speed can be estimated by observing its affects. Temperature is a measure of the energy of molecules. The more energy the molecules in air have, the hotter it feels. Relative humidity compares the actual amount of water vapor in the air with the maximum amount of water vapor the air can hold at that temperature (its capacity). Differences in air pressure cause Earth's winds and weather changes. Air pressure is simply the weight of the atmosphere per unit area. Air pressure is directed equally in all directions. Clouds have three simple names: Cirrus, Stratus, and Cumulus. These three names represent the three main cloud types. Cirrus clouds are high level clouds and due to high altitude, the water is almost frozen to form ice crystals. If there are isolated Cirrus clouds, they do not indicate any instability in the weather and may not bring rain. However, if the clouds are dense, they often indicate that a storm might be approaching. Both Stratus clouds and Cumulus clouds are low-level. Stratus clouds are layered clouds that usually bring a drizzle and there is widespread rain and in some cases ocean air. Cumulus clouds are neutral weather clouds. All the other clouds are combinations or variations of these types. Technology has greatly influenced the ease and accuracy of making weather predictions. Weather data at thousands of locations can be gathered instantaneously and applied to weather prediction models to produce weather maps. A cold front is the leading edge of a cooler air mass of air, replacing at ground level a warmer mass of air. The cooler, denser air wedges under the less-dense warmer air, lifting it. The upward motion causes lowered pressure along the cold front and can cause the formation of a narrow line of showers and thunderstorms when enough moisture is present. On weather maps, the surface position of the cold front is marked with the symbol of a blue line of triangles/spike pointing in the direction it is traveling. Cold fronts can move up to twice as fast as warm front and can produce sharper changes in the weather. Cold fronts are usually associated with an area of high pressure. A warm front is the leading edge of a warm air mass that displaces colder air, bringing a temperature increase and heavy rain where the front makes contact with the ground. On a weather map, a warm front is represented by a solid line with semicircles pointing towards the colder air and in the direction of the movement. On a colored weather map, a warm front is drawn with a solid red line.

Air Pressure differences

Uneven heating of earths surface causes air pressure differences. this sets air in motion.

Warmer air vs. Cooler air

Warmer air is less dense and has more pressure. Cooler air is more dense and less pressure. Warmer air will move towards cooler air, which results in winds.

how the cycling of water in and out of the atmosphere and atmospheric conditions relate to the weather patterns on Earth.

Water evaporates from the surface of the earth, rises and cools, condenses into rain or snow, and falls again to the surface. The water falling on land collects in rivers and lakes, soil, and porous layers of rock, and much of it flows back into the oceans. The cycling of water in and out of the atmosphere is a significant aspect of the weather patterns on Earth. Sunlight provides the energy that evaporates water from the surface of Earth. Some of the water vapor comes from the continents, but most comes from the oceans. Winds carry the water vapor from the ocean over the continents. Part of the water vapor condenses into clouds, then falls as rain or snow. Some of the rain returns to the ocean from rivers and streams as runoff. Some seeps into the ground to become groundwater. Some returns to the air by evaporation from the ground or by transpiration from plant leaves. When runoff from the continents returns to the ocean, one turn of the water cycle is completed. Other routes are possible. For example, water that evaporates from the ocean can return to the ocean as rain. The water cycle never ends. The salt water of the ocean supplies fresh water to the continents over and over again. Weather is the state of the atmosphere at a given time and place. A complete description of the weather includes the amount and type of clouds. Rain, snow, thunderstorms, lightning, and even dust storms are part of the weather. Measurements of temperature, air pressure, wind speed and direction, and the amount of moisture in the air are also included in a description of the weather. Weather is studied and predicted by scientists called Meteorologists. The science of meteorology is the study of the entire atmosphere, including the weather. To understand and predict the weather, meteorologist must first understand how the atmosphere heats and cools, how clouds form and produce rain, and what makes the wind blow.

weather balloons

Weather balloons are large balloons that are used to carry equipment high into the atmosphere. By doing this scientists can get a more accurate reading of temperature, humidity, and pressure at a specific altitude. Some balloons are designed to go 18 miles above the Earth's surface!

automated weather station

Weather data can also be gathered from the ground from weather stations. These stations can measure temperature, air pressure, relative humidity, rainfall, and wind speed/direction. Instruments: Thermometer, Barometer, Rain Gauge, Wind Vane, and Anemometer

low pressure

generally means cloudy, rainy weather. Air moves apart Warm air rises, clouds form

high pressure

generally means fair weather Air in upper atmosphere is sinking (cold, dense air) Warm, moist air cannot rise so no clouds