Weather & Climate 1401 Test #1

If you are located at 30° north on the Winter Solstice, what is the altitude of the sun above the horizon?

36.5 degrees Difference in latitude between your location and subsolar point = 30 + 23.5 = 53.5° Height above horizon = 90° - 53.5° = 36.5°

This manmade gas is used as refrigerants and propellants and is responsible for destroying the gas that shields the earth from ultraviolet radiation.

CFC's

This gas is absorbed by the oceans and through chemical reactions is converted to limestone rock.

carbon dioxide

This gas is the source of carbon for plants and releases oxygen when it is broken down during the process of photosynthesis.

carbon dioxide

This gas makes up most of the atmosphere of Venus - the planet with a temperature of about 870° F.

carbon dioxide

This is a somewhat variable gas that is responsible for 50% (most) of the Greenhouse Effect

carbon dioxide

The Earth's atmosphere contains gases and particulates, but no compounds.

false A compound is a substance formed from two or more elements that combine in constant proportions. Compounds, such as water vapor, carbon dioxide, methane and others are common in our atmosphere.

The minimum daily air temperature usually occurs near sunset.

false The minimum temperature occurs near sunrise because the Earth's surface has experienced a net loss of radiation through the night.

The thermosphere contains the ozone layer.

false The ozone layer is in the stratosphere.

The thermosphere is very hot because it contains a lot of greenhouse gases.

false The thermosphere contains virtually no greenhouse gases because the air at this altitude (50-105 miles) is so rarefied (99.9% of the atmosphere lies below the thermosphere). This layer is the hottest because it is in direct contact with incoming solar radiation.

The troposphere has the lowest density of gases.

false The thermosphere has the lowest density of gasses. The troposphere has the highest density of gases.

The layer of the atmosphere with the highest temperature is the mesosphere.

false The thermosphere is the hottest because it is in direct contact with incoming solar radiation.

It should be the coldest temperature in the late afternoon.

false Typically the coldest temperature occurs right before sunrise. This is the longest period of terrestrial radiation with no incoming insolation.

When energy is absorbed and reradiated from the Earth's surface, it is reradiated as shortwave radiation.

false it enters as shortwave radiation and is reradiated at longer wavelengths; i.e., as terrestrial, longwave, infrared radiation (TIR).

The atmosphere is heated directly by incoming solar radiation.

false it is heated by reradiated, terrestrial longwave infrared energy from the surface. It is heated from below!

The amount of this nongaseous material is increasing as a direct result of conversion of land to agricultural use and by the burning of forests and fossil fuels.

particulates

Air pressure is simply the weight of the air above you pushing down on you.

true

Daylight is the same at each line of latitude during the equinoxes (March 21 and September 23).

true

Some of the first organisms that added oxygen to the atmosphere include cyanobacteria and stromatolites.

true

The 500mb level is significant because it is where the steering winds occur and it is the halfway point, by volume, of the atmosphere.

true

The amount of water vapor in the atmosphere is temperature dependent.

true

The aurora are a product of the magnetosphere which is located in the thermosphere.

true

The coldest layer of the atmosphere is the mesosphere.

true

The environmental lapse rate (ELR) occurs in the troposphere.

true

The greenhouse effect is a nature occurrence. It occurs because certain gasses in the atmosphere act to absorb terrestrial radiation.

true

The wavelengths emitted by the earth (terrestrial radiation) are longer than those emitted by the sun.

true

The magnetosphere, ozone, clouds, and particulates act to shield the atmosphere.

true All of these are part of the impressive shield that Earth has surrounding it. Each of these acts in a different way to protect the Earth from harmful radiation, and to deflect is back into space.

The troposphere is considered the "weather zone".

true Almost all of the weather we have on earth takes place in the troposphere.

The formation of the ozone (O3) layer occurred in response to the development of photosynthesis by algae and plants.

true Because ozone, which is a tri-atomic oxygen (O3) molecule formed from oxygen, it follows that oxygen had to accumulate in the atmosphere before the ozone layer could form. Oxygen is released during photosynthesis when carbon dioxide is broken apart to form carbon and free oxygen.

Because Venus has a thick carbon dioxide atmosphere, it has high temperatures.

true Because the atmosphere of Venus is so thick and is made of heat-trapping carbon dioxide, the entire planet is hot and the temperature varies little from one region to another.

The height of the tropopause is greatest above the equator.

true Because the troposphere is warmer in the tropics, the air in that region rises to greater altitudes before being stopped by the overlying air in the stratosphere.

Generally speaking, the greater the height above the surface, the less water vapor there is in the atmosphere.

true Because water vapor is derived from the surface by evaporation, the amount of water vapor generally decreases with increasing elevation. Also, the lower temperatures at higher elevations in the troposphere result in cooling of the water vapor, and this leads to precipitation - which constitutes a loss of water from the sky. So, higher elevations have less water vapor.

All other factors being equal, the bigger the planet, the thicker its atmosphere.

true Big planets have stronger gravitational fields that can hold onto their atmospheric gases to a greater degree than can low mass planets.

Evaporation and transpiration are the earth's primary cooling processes.

true Both of these processes cool the environment around them. That is why a humid day feels hotter than a non-humid day. The sweat does not evaporate off your skin when it gets reallly humid.....more later.

An atmosphere that is rich in carbon dioxide traps a lot of heat energy because carbon dioxide is a greenhouse gas.

true Carbon dioxide is a greenhouse gas, which means that it absorbs insolation and thereby heats the atmosphere. So, the more carbon dioxide in the atmosphere, the warmer it is - all other factors being equal.

The amount of carbon dioxide in the atmosphere is greatest during the Northern Hemisphere's winter.

true Carbon dioxide levels are greatest in winter because less photosynthesis occurs at this time of the year. Photosynthesis removes carbon dioxide from the air.

If ozone were not present between 11 and 30 miles above the surface, clouds would develop upward to greater heights.

true Clouds can develop upward only as long as the air within them remains warmer than the surrounding air. Because ozone in the stratosphere traps heat, the stratosphere is warmer than the air in the upper troposphere, and this limits the vertical development of the clouds. If ozone were not present, there would be no stratosphere--and so clouds would rise to greater heights before the air within them cooled to the ambient air temperature.

Comets played a key role in shaping the composition of the earth's atmosphere, especially during its early history.

true Comets have a played an important role in shaping the atmosphere of the earth because they consist of frozen gases (while the comet is in space) that are added to the earth's atmosphere when the comets strike the earth. For example, comets have added a tremendous amount of water to the planet. Comets were more abundant in the early solar system and therefore played a bigger role in shaping the composition of the atmosphere at that time. Since then, volcanic out-gassing has become the dominant process - as it is today.

The magnetosphere is just one of many components of the atmosphere that help to shield the earth.

true Other components include the ozone layer, dust particles, water droplets/clouds, the ionosphere, etc.

The telegraph played an important role in improving the ability to make accurate weather forecasts.

true The invention of the telegraph in the 1840s made it possible to transmit information about weather conditions almost instantly to weather offices in distant locations. This "real-time" access to current weather conditions over a large area enabled meteorologists to develop a better understanding of weather events.

The sun should never be directly overhead (90 degree angle) here at Sam Houston State.

true The sun is only ever directly overhead (90 degrees) within the tropics (23.5 degrees north and south).

Locations near the coast will have smaller yearly temperature ranges than inland locations.

true The water holds heat longer, and it takes longer to heat up. Therefore, coastal areas will be warmer during the winter and cooler during the summer than inland locations that are at the same latitude.

Wind chill is just one example of "sensible" temperature.

true There is also the heat index, and the UV index.

The lowest temperature in the atmosphere occurs in the thermosphere.

false The lowest temperature occurs in the mesosphere.

Because Aristotle's ideas about the nature of the elements that comprised the physical world were wrong, his ideas contributed nothing to the development of our understanding of the world.

false Although his ideas about the exact nature of the elements were incorrect, his belief that nature was reducible to physical elements and forces that interacted to produce all of the things that comprise the natural world was a giant step forward in humanity's understanding of the world. Prior to his ideas, and those of other Greek philosophers, people believed that natural processes, such as storms, were the result of the actions of supernatural beings and supernatural forces. Why does it rain? The gods willed it. Why did we have storm last night? God was angry. So long as people believed that supernatural forces were responsible for everything, progress was impossible. The Greeks literally changed the way we think about the world and thereby opened the door to understanding it.

The philosophical approach that the Greeks used to develop their ideas about the nature of the world was all that was needed to lead to correct knowledge about the natural world.

false Although the Greeks were correct in attempting to explain the world in terms of natural processes, they did not perform experiments to determine if their philosophical explanations were correct. So, they took a step in the right direction, but didn't go far enough. The scientific method requires that we use logic, but that we also test our ideas to determine whether or not they are correct. This method was not developed until the Renaissance--more than 1800 years after Aristotle lived.

Climate is the weather extremes for a given time and place.

false Climate is the characteristic weather for a time and place.

The composition of the atmosphere is controlled entirely by physical and biological processes that are generated on, or within, the earth. In other words, the Earth is a "closed system" and nothing from outside of the Earth affects it's atmosphere.

false Impacts from comets, asteroids, and meteorites that came from space (i.e., from outside of the earth) have also significantly influenced the composition of the atmosphere - especially during its early history.

Mercury has the highest consistent temperature in the solar system.

false Mercury has the highest RANGE of temperatures, but Venus has the highest consistent temperature.

The Earth's atmosphere contained the current amount of oxygen by 6000 years ago.

false Present day levels of oxygen in the atmosphere occurred by about 500 million years ago.

People have always understood that storms move from one area to another.

false Prior to the 1700s, people once thought that storms were local phenomena caused by supernatural beings that either lived in the area or visited it.

A radiosonde is a special type of radar system that is specifically designed to detect tornadoes.

false Radiosondes are instrument packages carried by balloons and are designed to transmit information on temperature, pressure and relative humidity. Although this information is used to prepare analyses of weather conditions, their primary purpose is not to detect tornadoes.

A scientific theory is little more than an educated guess--which is why nonscientists should feel free to dismiss them if they don't like them.

false Scientific theories are far more than educated guesses. If an idea has been elevated to the status of a scientific theory, it has passed numerous tests designed to determine if it is true. Furthermore, scientific theories are capable of predicting things before they are discovered. For example, particle physicists predicted the existence of antimatter and numerous particles before they were discovered. In essence, the theory indicated that they should exist. Based on this, scientists looked for them--and found them. So, just because people may not like a particular theory, that is not sufficient grounds to dismiss it. Dismissal of a theory requires concrete evidence to disprove it--and that requires experimentation--not emotion. In short, a scientific theory stands or falls on the basis of evidence--not on whether we like it or dislike it.

The wavelengths emitted by the earth are shorter than those emitted by the sun.

false Terrestrial wavelengths are longer than solar wavelengths.

The normal (or environmental) lapse rate (ELR) applies to pressure changes.

false The ELR relates to temperature changes as you go up in the troposphere. For every 1000 ft increase in height, the temperature decreases by 3.5 degrees F.

The south pole has a period of 24 hours of darkness on December 21st.

false The South pole has a period of 24 hours of daylight on December 21st. It is the North pole that has a period of 24hr darkness on December 21st.

The age of instruments occurred during the 1800's.

false The age of instruments occurred during the 1700's. The 1800's was the period when scientists learned more about storms.

The atmosphere of the earth has always contained significant amounts of free oxygen (O2).

false The atmosphere has evolved through time as a result of various processes (see lecture notes and text). When it originally formed, the atmosphere consisted largely of methane and ammonia, and there was little free oxygen. Oxygen did not accumulate until photosynthesis evolved.

The aurora are generated within the stratosphere.

false The aurora are generated within the thermosphere because they require high temperatures in order to develop. In other words, the aurora occur because of the ionization of gases at high temperatures.

The aurora occur because of the ozone layer.

false The aurora, northern and southern lights occur due to the magnetosphere

The gas planets (Jovian) planets have rocky surfaces and thin atmospheres.

false The gas planets have no solid surface. Their thick atmospheres of hydrogen, helium, methane and ammonia change to an ocean of liquid hydrogen at a depth of several hundred miles below the top of the atmosphere.

Only less than 1 percent of the gasses in the earth's atmosphere play a role in weather. These gasses include Nitrogen and Oxygen.

false The gasses that affect weather do only consist of less than 1 percent of the total gasses, but they are carbon dioxide, water vapor, and particulates.

The troposphere contains the ionosphere.

false The ionosphere is located in the thermosphere.

The changing distance between the earth and the sun, which results from the ellipticity of the earth's orbit, is largely responsible for the seasonal changes in temperature.

false Please tell me that you got this question correct!!! The seasons are caused by the tilt of the earth and the different angle of the sun (causing different amounts of energy to reach the earth at certain times of the year) due to this tilt. Although the earth's distance from the sun varies from 91.5 million miles at perihelion, to 94.5 million miles at aphelion, the 3 million-mile difference is too small to produce changes in energy levels received at the earth sufficient to produce the seasons. The seasons result from a combination of the earth's 23.5° axial tilt relative to the ecliptic (the plane of the earth's orbit) and parallelism (the fact that the earth's axis always points in the same direction relative to the stars as it moves around the sun)- as discussed in the text.

This gas is produced by the decay of vegetation and by the digestive processes of cows and termites. It acts to heat the atmosphere.

methane

This is the most abundant gas in the atmosphere and is very inert. It is made available to plants by a process known as fixation.

nitrogen

This gas is the second most abundant non-variable gas and controls the intensity with which fires burn. It is released in the process of photosynthesis and can subsequently combine to form ozone (O3).

oxygen

This gas occurs in the stratosphere and is responsible for heating this layer when it absorbs UV radiation.

ozone

This gas protects us from harmful UV radiation.

ozone

When CO2 levels go up, plants growth is enhanced and this acts to return CO2 amounts to their original level. By the same token, if the amount of CO2 in the atmosphere goes down, plant growth declines, and this also acts to return the amount of CO2 to its original level. This combination of processes helps maintain the temperature of the planet at a level that suits life on earth.

true This is the basis for the Gaia hypothesis; i.e., the idea that feedback processes help control the temperature of the planet by controlling the amount of greenhouse gases in the atmosphere. The example cited in the question is an example of negative feedback; i.e., feedback which acts to restore a system to its original condition. Negative feedback is desirable. In contrast, positive feedback pushes a system away from a balanced state. As will be discussed later in the course, there are several forms of positive feedback which are currently acting to push the earth to a much warmer state than has existed since humans developed civilization. This is not a good thing to happen! Positive feedback in nature is bad.

The angle of the sun determines the amount of radiation that reaches the earth, and therefore the temperature.

true This is why it is cooler during the winter and warmer during the summer.

The Middle Ages were characterized by dogmatic beliefs that limited progress in developing a better understanding of the natural world.

true This period is also know as the "Dark Ages" because the "light of knowledge" was extinguished and progress basically stopped. In fact, some knowledge--such the fact that the earth is spherically shaped--was lost. This step backward occurred because people reverted to the belief that God, the Devil, angels and demons were directly responsible for natural processes--such as storms, earthquakes, droughts and so on. And, because people believed that it was sinful to spend time trying to understand the world (because it wasn't going to get them into heaven), questioning stopped and was replaced by dogma. Dogma consists of beliefs propounded by the Church that could not be questioned without fear of persecution, imprisonment, torture or death. Because of this, those that wanted to think about the world in natural terms were often too afraid to do so. So, knowledge stopped.

If you were in a hot air balloon basket at 5,000 feet, and the ground temperature is 70 degrees F, it would be 52.5 degrees F where you are.

true Use the formula for the ELR to calculate this.

Planet's with thin atmospheres, or no atmospheres, experience very large variations in temperature between the sunlit side and the side in darkness.

true With little or no atmosphere, there Is little or no gas to either block, trap or redistribute solar energy from sunlit areas to dark areas. Consequently, areas in the sunlight can become very hot relative to those in dark regions because there is no atmosphere to block the sunlight, but there is also no atmosphere to trap and redistribute the solar energy into dark areas. This means that planets with little or no atmosphere (such as Mercury) experience extreme temperature variation.

The sun crosses the equator twice a year.

true as the preceding discussion indicates, the sun crosses directly overhead at all locations between 23.5° N and S twice a year as it moves from one solstice position to the next - and this includes the equator.

On the summer solstice, the sun never sets for positions north of the Arctic Circle.

true even though the sun is low in the sky in areas north of 66.5° north latitude, these areas receive 24 hours of sunlight. *Make sure you understand why this is true.

This gas comprises 0.1 to 4% of the atmosphere by volume and it's amount in the atmosphere is determined to a large degree by temperature.

water