Exam 1

Question 1

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 inderstanding.

Answer 1

FalseAlthough 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.

Question 2

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.

Answer 2

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.

Question 3

THe Middle ages were characterized by dogmatic beleifs that limited progress in developing a better understanding of the natural world.

Answer 3

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.

Question 4

THe scientific method was developed by the Greeks, but was then lost during the middle ages.

Answer 4

False - As discussed in the answer the question #2, the Greeks limited their thinking to philosophical arguments based on premises that they never tested. It was not until the Renaissance that the scientific method began to be used. This began at various times in various places in Europe from roughly the 1400’s to the 1600’s

Question 5

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

Answer 5

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.

Question 6

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

Answer 6

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.

Question 7

THe most abundant gas in the atmosphere and is very inert. Made available to plants by fixation.

Answer 7

nitrogen

Question 8

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

Answer 8

ozone

Question 9

this is a variable gas that is responsible for 50% of the greenhouse effect

Answer 9

carbon dioxide

Question 10

this gas comprises0.1 to 4% of the atmosphere by volume and it’s amount in the atmosphere is determined to a large degree by temperature

Answer 10

water

Question 11

this manmade gas is used as refrigerants and propellants and is responsible for for destroying the gas that shields the earth from uv radiation

Answer 11

CFCs

Question 12

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

Answer 12

carbon dioxide

Question 13

This gas is produced by the decay of vegetation and by the digestive processes of cows and termites

Answer 13

methane

Question 14

this gas is the source of carbon for plants and releases oxygen when it is broken downduring the process of photosynthesis

Answer 14

carbon dioxide

Question 15

this gas protects us from harmful UV radiation

Answer 15

ozone

Question 16

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

Answer 16

carbon dioxide

Question 17

this gas is the second most abundant non variable gas and controld the intensity with which fires burn. It is released in the process of photosynthesis and can subsequently combine to form ozone

Answer 17

oxygen

Question 18

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

Answer 18

particulates

Question 19

the layer of the atmosphere with the highest temperatures

Answer 19

THERMOSPHERE

Question 20

THe layer in which weather occurs

Answer 20

TROPOSPHERE

Question 21

The layer in which mixing of air occurs

Answer 21

TROPOSPHERE

Question 22

The layer that contains ozone

Answer 22

STRATOSPHERE

Question 23

THe coldest layer of the atmosphere

Answer 23

MESOSPHERE

Question 24

THe layer with the lowest density of gases

Answer 24

MESOSPHERE

Question 25

THe layer in which the ionosphere is located

Answer 25

THERMOSPHERE

Question 26

The layer in which aurora occur

Answer 26

THERMOSHERE

Question 27

The atmpsphere of the earth has always contained significant amounts of free oxygen

Answer 27

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.

Question 28

Planets with thin atmospheres, or no atmospheres, experience very large variations in temp. between the sunlit side and the side in darkness

Answer 28

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.

Question 29

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

Answer 29

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.

Question 30

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

Answer 30

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

Question 31

THe Earth’s atmosphere contains gases and particulates, but no compounds

Answer 31

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.

Question 32

The formation of the ozone layer occured in response to the development of photosynthesis by algae and plants

Answer 32

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.

Question 33

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

Answer 33

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.

Question 34

THe amount of carbon dioxide in the atmosphere is greatest during the Northern Hemisphere’s winter

Answer 34

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.

Question 35

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

Answer 35

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.

Question 36

THe height of the tropopause is greatest above the equator

Answer 36

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.

Question 37

If ozone were not present between 11 and 30 miles above the surface, clouds would deveop upward to greatere heights

Answer 37

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.

Question 38

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

Answer 38

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.

Question 39

The aurora are generated within the stratosphere

Answer 39

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.

Question 40

Comets played a key role in shaping the composition of the eath’s atmosphere especially during its early history

Answer 40

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.

Question 41

According to James Lovelock, the originator of the Gaia hypothesis, the eath is, in some sense, a conscious being and is capable of making decisions regarding the regulation of the earths atmospheric composition

Answer 41

False - Although some New Age groups have claimed that Gaia is alive and conscious, this is not what Lovelock suggested. As used by him, Gaia is a metaphor that refers to a set of feedback processes that operate automatically–but without conscious thought or deliberate purpose–to regulate conditions that maintain a viable biosphere.

Question 42

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

Answer 42

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.

Question 43

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 temp of the planet at a level that suits life on earth.

Answer 43

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.

Question 44

A scientific theory is little more than an educated guess

Answer 44

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.

Question 45

The gas planets have rocky surfaces and thin atmospheres

Answer 45

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.

Question 46

Because venus has a thick carbon dioxide atmosphere, it has high temperatures

Answer 46

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.