The Atmosphere and Atmospheric Effects
Resources: University of California, Irvine, Dept of Chemistry; Centre for Atmospheric Science, University of Cambridge; Okanagan University College; Geosciences Research Institute; Rensselaer Polytechnic Institute; Rice University; Australia Ultralight Federation; windpower.dk; NASA; University of New Mexico; University Corporation for Atmospheric Research; Department of Atmospheric Sciences, University of Illinois, Urbana;
2.4 Energy in the Earth System
Diagram the water cycle and describe interrelationships of surface and subsurface
b. Explain daily and seasonal changes in the sky (i.e., the sun's position and the intensity and duration of sunlight)
c. Analyze the uneven heating of Earth by the sun
d. Discuss the effects of air movements on weather
e. Explain how differences in atmospheric pressure determine direction of air movement
f. Describe the energy transfer process of convection, conduction and radiation in relation to the atmosphere/ocean and Earth's interior structure
g. Interpret weather map data to predict weather patterns
1. Groundwater and the Hydrologic Cycle- Hydrologic Cycle takes you to a single page review.
Introduction (From University of New Mexico)
Water is vital to all living things on the Earth and though there appears to be an abundance of water on the globe (about 1.46 trillion cubic kilometers) the amount of water usable to humans is diminishing. Change in the location and state of water on the Earth is part of a natural process that is called the hydrologic cycle
Although the hydrologic cycle is operating constantly and will never end, human activities constitute a major interference in the natural process. Human activity that has impacted the natural cycle include:
As human population increases and the amount of usable water decreases, water rights and conservation will likely be a prominent issue in local, state, national and international policies.
- Alteration of runoff through construction of paved areas
- Changes in global climate and resulting melting of glaciers
- Increased evaporation due to irrigation in arid areas (like New Mexico)
Groundwater is water that infiltrates through the surface of the Earth and resides in pores or cracks in the subsurface. Underground waters constitute approximately 1.05% of the total water in the Earth. Groundwater resides in small open spaces such as pores or fractures below the Earths surface except where large caves (Carlsbad Link here) have formed due to dissolution of the surrounding rocks. The amount of open space available for water is referred to as the porosity. Rocks with a high porosity include sandstone where the volume of pore space can be as high as 30%. In unfractured bedrock, porosity can be below 10%. Permeability is another important characteristic of materials and refers to the ability of a solid to allow fluids to pass through. A rock or sediment with high (or good) permeability has many pores that are well connected so that water can pass easily through the material. A good water reservoir has both high permeability and porosity.
The groundwater table is the boundary that separates an upper zone where air and water occupy pores from a lower zone where all pores are saturated with water. The upper zone is referred to as the unsaturated zone; the lower zone is the saturated zone. The depth to the groundwater table depends on several factors including the rate of discharge and recharge, time of year, the topography and the local geology. Dramatic changes in the groundwater table due to over pumping of water wells can have many serious negative effects such as ground subsidence, formation of fissures and sinkholes, reduction in groundwater quality and, near the oceans edge, incursion of salt water into freshwater aquifers. In areas where withdrawal of groundwater exceeds recharge of the source, a cone of depression (link to photo or site) that has a shape of an inverted cone forms and the water level in the well is depressed below the water table. Administering to problems of mining groundwater (that is, when withdrawal of water exceeds recharge) is very difficult and, as in the case of ground subsidence, the effects may be irreversible. Decreasing withdrawal is the clearest solution to problems in balancing recharge and discharge of groundwater. Injecting water into source areas has also been proposed for some areas.
Caves and Karst Topography
Most groundwater exists between pores and spaces in sediments or within fractures of bedrock. However, in areas where limestone is abundant and rainfall is sufficient groundwater may be a significant erosion agent producing large cavities and caves. The dissolution of limestone to form caves is enhanced in part due to the mixing of water and atmospheric carbon dioxide to form a weak acid called carbonic acid. Limestone begins to dissolve as water seeps into cracks and fissures resulting in formation of larger and larger cavities. The erosive power of the water may also be enhanced by combination of water with carbon dioxide form organisms and plants within the soil. Formation of stronger and more corrosive sulfuric acid may also occur where sulfur-producing organisms exist. The amount of limestone removed may be immense considering that some caves are kilometers in length.
More information on caves and cave formation can be found at:
National Caves Association Welcomes You!
Carlsbad Caverns National Park: Official Home Page
Karst topography is found in areas where limestone occurs near the Earths surface and is characterized by sinkholes, caverns and paucity of surface streams. Dissolution of limestone leading to formation of karst topography is facilitated in areas with high-rainfall, abundant vegetation, and fractured limestone. Karst topography is found in Indiana, Kentucky and Florida. The following links show images and more information on karst topography.
Florida Karst Topography
Karst Topography Paper Model -click on "Paper Model"
Click here for a more detailed account of the water cycle and it's relationship to the surface and subsurface reservoirs.
2. The Seasons
Earth/Sun relationship at the equinoxes and solstices- Animation- tilt of the earth and position around the Sun
Details of Seasons
Characteristics of Seasons
- Summer- (solstice) Earth farthest away from the Sun; Northern Hemisphere- Points toward the sun; More daylight hours than hours without sun; It is winter solstice in the Southern Hemisphere because the southern hemisphere points away from the sun
- Fall- (equinox) Equal hours of daylight and night; The southern hemisphere also has equal day and night but it is the Spring equinox
- Winter- (solstice)- Earth is closest to the Sun at winter solstice but because the northern hemisphere points away from the Sun, we experience winter; There are fewer daylight than night hours; The southern hemisphere points toward the Sun, therefore, it is Summer Solstice
- Spring- (equinox)- Equal hours of daylight and night; The southern hemisphere also has equal day and night hours except it is the Fall equinox
3. Uneven Heating of the Earth
Energy Distribution from the sun
Atmospheric Energy Content (a more detailed description)
When the new page opens, click on the following: 1.1-1.7 1.9, 1.11, 1.13
Energy Heat Transfer- Modified from University Corporation for Atmospheric research
Practically all of the energy that reaches the earth comes from the sun. Intercepted first by the atmosphere, a small part is directly absorbed, particularly by certain gases such as ozone and water vapor. Some energy is also reflected back to space by clouds and the earth's surface. - See graphic- scroll down to see...
Energy is transferred between the earth's surface and the atmosphere via conduction, convection, and radiation. Details and examples of each of these methods are found in Part 6 below.
Conduction is the process by which heat energy is transmitted through contact with neighboring molecules.
Some solids, such as metals, are good conductors of heat while others, such as wood, are poor conductors. Air and water are relatively poor conductors.
Since air is a poor conductor, most energy transfer by conduction occurs right at the earth's surface. At night, the ground cools and the cold ground conducts heat away from the adjacent air. During the day, solar radiation heats the ground, which heats the air next to it by conduction.
Convection transmits heat by transporting groups of molecules from place to place within a substance. Convection occurs in fluids such as water and air, which move freely.
Radiation is the transfer of heat energy without the involvement of a physical substance in the transmission. Radiation can transmit heat through a vacuum like that found in space.
Energy travels from the sun to the earth by means of electromagnetic waves. The shorter the wavelength, the higher the energy associated with it. This is demonstrated in the animation below. As the drill's revolutions per minute (RPMs) increase, the number of waves generated on the string increases, as does the oscillation rate. The same principle applies to electromagnetic waves from the sun, where shorter wavelength radiation has higher energy than longer wavelength radiation.
Most of the sun's radiant energy is concentrated in the visible and near-visible portions of the spectrum. Shorter-than-visible wavelengths account for a small percentage of the total but are extremely important because they have much higher energy. These are known as ultraviolet wavelengths.
4. Effects of Air Movements on Weather
Introduction to the atmosphere- Composition and structure
Graphic of atmospheric layers and events/characteristics in each
Temperature and pressure associated with the layers of the Earth's atmosphere
Why is the pressure highest in lower regions of Earth's atmosphere?
The reason is because gravity holds the major portion of the atmosphere closest to the earth where living things need it. Where there are greater numbers of air molecules, there are greater numbers of collisions between them and higher pressure.
Earth's early atmosphere- Advanced discussion
Evolution of earth's atmosphere- Advanced discussion
Specific Heat is the ratio of the heat capacity of a substance to the heat capacity of a reference substance, usually water. Heat capacity is the amount of heat needed to change the temperature of a unit mass 1°. The heat capacity of water is 1 calorie per gram per degree Celsius (1 cal/g-°C) or 1 British thermal unit per pound per degree Fahrenheit (1 Btu/lb-°F). Thus, the specific heat of some other substance relative to water will be numerically equal to its heat capacity; for this reason, “specific heat” is often used when the heat capacity actually is meant. Because the heat capacities of most substances vary with changes in temperature, the temperatures of both the specified substance and the reference substance must be known in order to give a precise value for the specific heat. The heat capacity of water at 15°C is a frequently used value. Like specific gravity, specific heat is a dimensionless quantity, i.e., a pure number having no unit of measurement associated with it.
Latent Heat - hidden heat during phase changes (solid to liquid to gas) It is heat associated with a change of state or phase (see states of matter ). Latent heat, also called heat of transformation, is the heat given up or absorbed by a unit mass of a substance as it changes from a solid to a liquid, from a liquid to a gas, or the reverse of either of these changes. It is called latent because it is not associated with a change in temperature. Each substance has a characteristic heat of fusion, associated with the solid-liquid transition, and a characteristic heat of vaporization, associated with the liquid-gas transition. The latent heat of fusion for ice is 80 calories per gram (see calorie ). This amount of heat is absorbed by each gram of ice in melting or is given up by each gram of water in freezing. The latent heat of vaporization of steam is 540 calories per gram, absorbed during vaporization or given up during condensation . For a substance going directly from the solid to the gas state, or the reverse, the heat absorbed or given up is known as the latent heat of sublimation .
Phases of Matter- including pressure effects on metling point and phase diagrams
Latent Heat --application to weather
Cyclones and anticyclones -Summary
Cold-core cyclone: a weather system characterized by deepening low pressure center with altitude. The thickness between pressure surfaces, which is directly proportional to the layer temperature, is lowest at the center of the low. The low pressure center aloft is located left that at the surface in a wave cyclone. BAD WEATHER
Warm-core cyclone: a weather system characterized by the thermal lows that are stationary, have no fronts and are associated with very hot, dry air. The shallow near-surface cyclonic circulation weakens and then reverses with altitude.
Anticyclone: a weather system characterized by relatively high surface pressure compared with the surrounding air; surface winds blow clockwise in the Northern Hemisphere (counter-clockwise in the Southern Hemisphere) and outward that is associated with divergence, and therefore sinking motion, and a fair weather. GOOD WEATHER
Cold-core anticyclone: a shallow weather system that coincides with the dome of continental polar or arctic air. They are responsible for the frigid temperatures over the continental US in winter. They are shallow systems in which the clockwise circulation weaken with altitude and often reverses.
Warm-core anticyclones: a weather system characterized by strengthening high pressure center with altitude. The thickness between pressure surfaces is highest at the center of the high. The semiperminent subtropical anticyclones, such as Bermuda-Azores high, are examples of warm-core anticyclones which are accompanied by subsiding, warm, dry air.
A thunderstorm associated with lifting of air along the surface of front is called frontal thunderstorm. Most are triggered by vigorous uplift of maritime tropical (mT) air along or ahead of a well-defined cold front. Frontal thunderstorms that are associated with a warm front can produce snow in winter.
Cloud Formation- Use for weather map study below (symbols for cloud types)
5. Explain how differences in atmospheric pressure determine direction of air movement- Global winds move from high pressure to low pressure but in a circular and repeated motion. These winds follow the same pattern as sea and land breezes through onshore or offshore air aloft processes. See land and sea breezes below.
At low pressure areas air rises and is drawn toward a high pressure area in a cyclical process. As the air rises, cloud formation occurs and ultimately precipitation. This gives stormy weather. High pressure areas bring fair weather. See more detail of cyclones and anticyclones below.
The pressure gradient, or change between the core of the anticyclone and its surroundings, combined with the Coriolis effect , causes air to circulate about the core in a clockwise direction in the Northern Hemisphere and a counterclockwise direction in the Southern Hemisphere. Near the surface of the earth the frictional drag of the surface on the moving air causes it to spiral outward gradually toward lower pressures while still maintaining the rotational direction. This outward movement of air is fed by descending currents near the center of the anticyclone that are warmed by compression as they encounter higher pressures at lower altitudes. The warming, in turn, greatly reduces the relative humidity, so that anticyclones, or “highs,” are generally characterized by few clouds and low humidity. Fair weather occurs at anticylones. The term anticyclone is derived from the fact that the associated rotational direction and general weather characteristics of an anticylone are opposite to those of a cyclone .
Cyclones are commonly referred to as “lows.” atmospheric pressure distribution in which there is a low central pressure relative to the surrounding pressure. The resulting pressure gradient, combined with the Coriolis effect , causes air to circulate about the core of lowest pressure in a counterclockwise direction in the Northern Hemisphere and in a clockwise direction in the Southern Hemisphere. Near the surface of the earth, the frictional drag on the air moving over land or water causes it to spiral gradually inward toward lower pressures. This inward movement of air is compensated for by rising currents near the center, which are cooled by expansion when they reach the lower pressures of higher altitudes. The cooling, in turn, greatly increases the relative humidity of the air, so that “lows” are generally characterized by cloudiness and high humidity; they are thus often referred to simply as storms (bad weather).
6. Describe the energy transfer process of convection, conduction and radiation in relation to the atmosphere/ocean and Earth's interior structure
Atmospheric Processes- Modified from University Corporation for Atmospheric Research
Interactions - Atmosphere and Ocean
Water is an essential part of the earth's system. The oceans cover nearly three-quarters of the earth's surface and play an important role in exchanging and transporting heat and moisture in the atmosphere.
You may have figured out by now that the oceans and atmosphere interact extensively. Oceans not only act as an abundant moisture source for the atmosphere but also as a heat source and sink (storage). Click here to see excellent graphics of the relationship of all factors to heat transfer.BE SURE YOU SEE ALL GRAPHICS TO THE BOTTOM OF THE PAGE.
The exchange of heat and moisture has profound effects on atmospheric processes near and over the oceans. Ocean currents play a significant role in transferring this heat toward the poles. Major currents, such as the northward flowing Gulf Stream, transport tremendous amounts of heat poleward and contribute to the development of many types of weather phenomena. They also warm the climate of nearby locations. Conversely, cold southward flowing currents, such as the California current, cool the climate of nearby locations. All of these factors govern both the climate and weather in a particular area.
Ocean Currents and Climate
Radiation - atmosphere
Relation to Earth's Interior- Introduction
Earth Systems: Conduction- Earth's interior
Earth Systems: Convection- Earth's interior
Earth Systems: Radiation- Sun and Earth
Click here to see excellent summary and graphics of how the atmosphere, ocean and interior of the Earth work together to affect energy transfer throughout the oceans, land and atmosphere.
Types of thunderstorms. Click on each of the links to learn more
- A USATODAY.com graphic gives the basics on what thunderstorms are.
- The most common kind of thunderstorms are multicell cluster thunderstorms, which consist of cells are various stages of their life cycles occurring at the same time.
- A USATODAY.com graphic shows how "dry" thunderstorms can start forest fires.
- Characteristics of a storm/Types of lightning discharges
- Lightning Investigations
- High altitude research
- Ground-based research
- Global studies
- Global electric circuit
- Optical transient detector
- The future of lightning detection
- Severe thunderstorm safety
Tropical StormsHurricanes- HOW THEY ARE BORN- When the new window opens, click on the image of the hurricane like the one shown to the left to access the animation
- History Behind the Ozone Hole
- Recent Ozone Loss over Antarctica
- Science of the Ozone Hole
- Current Research Work
Reducing Fuel Impurities
7. Interpret weather map data to predict weather patterns
Reading weather maps
Learn to convert your local time to the standard used by all meteorologists. -4 pages (click on right arrow at bottom of each page to continue)
See how temperatures measured in Kelvin, Celsius and Fahrenheit are related.
Atmospheric pressure module: 7 pages- learn about pressure and temperature
Pressure Gradient Force- Winds
Coriolis force- Movie
Gradient Wind- wind blowing parallel to isobars
Winds Near the Surface- Affected by friction
Boundary Layer Winds
Offshore Flow Aloft
Sea Breeze Develops
Onshore Flow Aloft
Land Breeze Develops
Hurricanes- General Information
Learn how to read maps containing weather observation information for the surface - 7 pages (click on right arrow at bottom of each page to continue)
Learn how to interpret the WW2010 surface weather maps - 2 pages: Instructions: After reading the information on each page, click on "Current Weather Map" and then on ANIMATE at the bottom of the current weather map. Choose 24 frames or more and then click on the Play icon that appears. The lower right button on the map terminates your session.
Symbols on Maps- Overview
Observed dew point temperature
Observed Sea Level Pressure
Cold Front- 5 pages (don't miss animation on last page)
Warm Front- 5 pages (check out animation on last page)
850 millibar(mb) Advection
Geopotential Height-Height of a given pressure
Clouds and precipitation- Summary page
States of Water
Rising Air- 6 pages
High Level Clouds- 2 pages
Mid Level Clouds
Low Level Clouds - 2 pages
Fair Weather Cumulous Clouds
Other Clouds- 5 pages
Rain and Hail
Dangers to People
Dangers to the Environment
Regions of Freezing Rain
The Formation of Freezing Rain
Cyclones and Fronts
Anticyclones, Lee Troughs and Inverted Troughs
Cold-Air Damming and Extended Lows
Forecasting Freezing Rain
Upper Air Soundings
Warm Rain Processes
SWRP Sounding- predictions
El Nino- general information
Most recent El Nino
Non-El Nino Years
El Nino Events
Sea Surface Temperatures
Impacts on the Weather
Detection and Prediction of
ACCESS CURRENT WEATHER DATA AND INTERPRET CURRENT CONDITIONS- Correlate with the WW2010 Surface Weather Maps above and locate fronts, cyclones and anticyclones as well as the movement of these factors. Make a prediction about weather in YOUR LOCAL AREA using this resource. Go into weather archives to locate the maps during severe storm conditions and study the maps so you can recognize the different features.
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