Astronomy Chapter 10

Which of the following is not an expected consequence of the rising carbon dioxide concentration or global warming?

Animal deaths due to carbon dioxide poisoning.

What motivated Arrhenius to calculate how changes in carbon dioxide might affect the climate?

He was seeking to understand the causes of ice ages.

What kind of gas is most affected by thermal escape?

light gases

Where is most of the CO2 that has outgassed from Earth's volcanoes?

locked up in rocks

Convection occurs in the troposphere but not in the stratosphere because

lower altitudes of the troposphere are warmer than higher altitudes, unlike in the stratosphere.

The sky is blue because

molecules scatter blue light more effectively than red light.

Which of the following is not a product of outgassing?

oxygen

Which of the following gases absorbs ultraviolet light best?

ozone

What causes the release of oxygen into Earth's atmosphere?

photosynthesis

Which region of Earth has warmed the most in recent decades?

the Arctic

What are fossil fuels?

the carbon-rich remains of plants that died millions of years ago

What is the exosphere?

the highest layer in the atmosphere

What is the troposphere?

the lowest layer in the atmosphere

What is the thermosphere?

the part of the atmosphere that absorbs X rays

What is the stratosphere?

the part of the atmosphere that absorbs ultraviolet

The proper order of the layers of a generic atmosphere from lowest altitude to highest is

troposphere, stratosphere, thermosphere, exosphere.

The energy that warms Earth's surface comes primarily in the form of __________.

visible light from the Sun

Why is Mars red?

Its surface rocks were rusted by oxygen.

Which process is the primary source of the atmospheric gases on Earth?

outgassing from volcanoes

From where did the molecular oxygen in Earth's atmosphere originate?

photosynthesis from single-celled organisms

What kind of light warms the stratosphere?

ultraviolet

X rays from the Sun's corona

are absorbed in Earth's thermosphere.

Where is most of the water on Mars?

in its polar caps and subsurface ground ice

Why does the burning of fossil fuels increase the greenhouse effect on Earth?

Burning releases carbon dioxide into the atmosphere.

Why does Venus have such a great difference in temperature between its "no atmosphere" temperature and its actual temperature?

It has a large amount of greenhouse gases in its atmosphere.

As discussed in the video, the leading hypothesis for why Mars changed holds that interior cooling led to loss of its magnetosphere, allowing the solar wind to strip atmospheric gas away. How has the MAVEN mission provided evidence for this hypothesis?

It has measured rates of gas loss from the atmosphere today.

What is the leading hypothesis for Venus's lack of water?

Its water molecules were broken apart, and hydrogen was lost to space.

All of the following statements are true. Which one explains why Mars has lost so much more interior heat than Earth.

Mars is smaller than Earth.

Based on the evidence that atmospheric carbon dioxide is a cause of planetary warming, what aspect of the graphs should most concern us?

The carbon dioxide concentration today is significantly higher than at any time in the past 800,000 years and is rapidly rising.

Venus may have started with an ocean's worth of water. Where is its water now?

The water was lost when ultraviolet light broke apart water molecules and the hydrogen escaped to space.

Notice that the peaks and troughs on the temperature graph occur at the about the same times as peaks and troughs on the carbon dioxide graph. What can we infer from this fact alone?

There is a correlation between the carbon dioxide concentration and the global average temperature.

The atmosphere on Mercury is due to

bombardment

There are no aurora on Venus because it

lacks a strong magnetic field.

Ultraviolet light is absorbed in the

stratosphere.

Sunsets are red because

sunlight must pass through more atmosphere then, and the atmosphere scatters even more light at bluer wavelengths, transmitting mostly red light.

The greenhouse effect occurs in the

troposphere

The average temperature over the past 1000 years has been about 15∘C. From the graphs, you can conclude that Earth's average temperature during the past 800,000 years has __________.

varied between about 7∘C and 19∘C

The ionosphere is a layer of ionized gas that is

within the thermosphere.

Earth outgassed as much carbon dioxide as Venus, but it is locked up in the oceans and rocks.

True

One bar of atmosphere is roughly equal to Earth's atmospheric pressure at sea level.

True

Venus has a thicker atmosphere than Earth.

True

Now click the second tab (labeled "Terrestrial Planet Temperatures"), then explore what happens as you click the button that allows you to add or remove greenhouse gases. Which terrestrial planet would have its surface temperature the most dramatically changed if its greenhouse gases were removed from its atmosphere?

Venus

Which of the following worlds has the greatest difference in temperature between its "no atmosphere" temperature and its actual temperature?

Venus

Which of the following worlds has the most substantial atmosphere?

Venus

Which terrestrial world has the most atmosphere?

Venus

Listed following are characteristics of the atmospheres of Venus, Earth, and Mars. Match each atmospheric characteristic to the appropriate planet.

Venus -almost no surface winds -sulfuric acid clouds -runaway greenhouse effect Earth -atmosphere composed primarily of nitrogen -ultraviolet-absorbing stratosphere Mars -extremely low density atmosphere -global dust storms

Which planet(s) have an atmosphere that consists mostly of carbon dioxide?

Venus and Mars

All of the following statements are true. Which one provides strong observational support for the claim that greenhouse gases make a planet warmer than it would be otherwise?

Venus has a higher average temperature than Mercury.

Which of the following correctly lists the terrestrial worlds in order from the thickest atmosphere to the thinnest atmosphere? (Note: Mercury and the Moon are considered together in this question.)

Venus, Earth, Mars, Moon/Mercury

Geological evidence points to a history of extended ice ages in Earth's history. How did Earth recover from this snowball phase?

Volcanoes continued to inject CO2 into Earth's atmosphere, increasing the greenhouse effect to the point where ice melted.

Based solely on an understanding of the greenhouse effect (as displayed in the figure), which one of the following statements is true?

We should expect an increase in the greenhouse gas concentration to lead to global warming.

What is the difference in meaning between the terms weather and climate?

Weather refers to short-term variations in conditions, and climate refers to long-term variations in conditions.

In which direction do hurricanes in the Southern Hemisphere rotate?

clockwise

What are greenhouse gases?

gases that absorb infrared light

The greenhouse effect raises Earth's surface temperature (from what it would be otherwise) because the infrared light radiated by Earth's surface __________.

is absorbed by greenhouse gases, slowing the escape of this energy to space

Click the third tab (labeled "Global Warming"), then explore the graph and the expanded views you will find by clicking the "?" buttons. Which of the following statements are supported by the data shown?

-Earth's global average temperature has generally risen over the past century. -Atmospheric carbon dioxide levels have risen dramatically over the past century. -Rises in global average temperature tend to be closely associated with rises in atmospheric carbon dioxide concentration.

All the following statements are true. Which two represent the two facts that lead us to expect Earth to be warming up as a result of human activity? Be sure to choose two of the statements below.

-Human activity is increasing the concentration of carbon dioxide and other greenhouse gases in the atmosphere. -Greenhouse gases make Earth warmer than it would be otherwise.

Match the words at the left to the correct blanks in the sentences at right. You may use words more than once.

-The "edge of space" occurs in the layer we call the exosphere. -X-rays from the Sun are absorbed primarily in Eath's thermosphere. -Convection and weather occur primarily in Eath's troposphere. -Ultraviolet light from the Sun is absorbed primarily in Eath's stratosphere. -The greenhouse effect causes warming primarily in Earth's troposphere.

The following images show the four terrestrial planets in our solar system (not to scale). Rank these planets from left to right based on the atmospheric pressure at the surface, from highest to lowest.

-Venus -Earth -Mars -Mercury

The following images show the four terrestrial planets in our solar system (not to scale). Rank these planets from left to right based on the total amount of gas in their atmospheres, from most to least.

-Venus -Earth -Mars -Mercury

Although the data show only a correlation between the carbon dioxide concentration and the global average temperature, scientists have other reasons to think that a rise in the carbon dioxide concentration actually causes a rise in the global average temperature. All of the following statements are true. Which statements lend support to the idea that carbon dioxide is a cause of planetary warming? Check all that apply.

-We understand the physical mechanism of the greenhouse effect, through which carbon dioxide can increase a planet's temperature. -Models of the greenhouse effect successfully predict the temperatures of Venus and Mars from their atmospheric carbon dioxide amounts. -Models of Earth's climate that include recent increases in the carbon dioxide concentration match observed temperature increases better than those that do not include it.

Click on the first tab at the top of the interactive figure (labeled "The Greenhouse Effect"), then explore what happens as you click among the buttons (labeled "none," "low," "medium," and "high") that adjust the greenhouse gas concentration. Which of the following occur as the greenhouse gas concentration increase?

-more infrared light is absorbed in the lower atmosphere -the average surface temperature rises

Put the major layers of Earth's atmosphere in to the correct order from the ground upward. Drag the layers into place in the correct order from lowest altitude at left to highest altitude at right.

-troposphere -stratosphere -thermosphere -exosphere

Earth's temperature remains fairly steady, which means that Earth must return nearly the same amount of energy to space that it receives from the Sun. In what form(s) does Earth return most of this energy to space? Check all that apply.

-visible light reflected by clouds -visible light reflected by the surface -infrared light emitted by the surface and atmosphere

Match the words in the left-hand column to the appropriate blank in the sentences in the right-hand column. Use each word only once.

1. Most of the charged particles from the Sun are deflected around Earth by the magnetosphere. 2. Earth's stratosphere absorbs most of the ultraviolet light arriving here from the Sun. 3. Most of the X-rays coming from the Sun are absorbed in the thermosphere. 4. Gas particles in Earth's atmosphere most easily escape from the exosphere. 5. The densest layer of the atmospheres of Venus, Earth, and Mars is the troposphere.

Suppose Earth's atmosphere had no greenhouse gases. Then Earth's average surface temperature would be

250 K, which is well below freezing.

Make a prediction: If the rise in carbon dioxide concentration continues at its current pace, the concentration in the year 2050 will be about _____ parts per million.

460

Earth's stratosphere is heated primarily by which process?

Absorption of ultraviolet radiation by ozone.

Which of the following statements about the greenhouse effect is true?

All of the above are true.

How does the greenhouse effect work?

Greenhouse gases transmit visible light, allowing it to heat the surface, but then absorb infrared light from Earth, trapping the heat near the surface.

Of the four gases CO2, H2O, N2, and O2, which are greenhouse gases?

CO2 and H2O

Click the fourth tab (labeled "Computer Models"), then explore how the graph changes as you click among the three buttons to its left. What is the primary message of the full graph (with all three curves shown)?

Climate models successfully reproduce the major recent trend in temperature data only if both human and natural factors are included.

As you found in Part A, early Mars had both core convection and a strong magnetosphere. What is the connection between these two things?

Core convection helps generate a magnetic field, and the magnetic field creates the magnetosphere.

Each of the following statements was either true for Mars in the distant past (early Mars) or is true for Mars today. Sort the statements by dragging each into the correct bin.

Early Mars -some craters held lakes of water -strong greenhouse effect -strong magnetosphere -substantial volcanism and outgassing -core convection Mars Today -surface pressure too low for stable liquid water -solar wind strips atmospheric gas -very weal greenhouse effect

Which of the following planets has a stratosphere?

Earth

The Moon has no detectable atmosphere.

False

How is the atmosphere of a planet affected by the rotation rate?

Faster rotation rates produce stronger winds.

What key process underlies why Mars changed so much from its early conditions to its conditions today?

Interior cooling

Which of the following best describes rain on Venus?

It has sulfuric acid rain in its atmosphere, but the drops evaporate before hitting the surface.

What happens to the energy that the ground absorbs in the form of visible sunlight?

It is returned upward in the form of infrared light.

Why doesn't Mars have a stratosphere?

It lacks a layer of ultraviolet absorbing gas.

Deuterium is more abundant on Venus than elsewhere in the solar system. What do we think this fact tells us about Venus?

It once had huge amounts of water in its atmosphere.

On a cloudless day, what happens to most of the visible light headed toward Earth?

It reaches Earth's surface, where some is reflected and some is absorbed.

Imagine that you visit an alien world that has an atmospheric composition similar to that of Earth (that is, mostly nitrogen and oxygen) and a surface atmospheric pressure of 1.2 bars. Which of the following statements best describes the effects of this pressure?

It will feel quite similar to the atmospheric pressure on Earth.

Which of the following planets has the least substantial atmosphere?

Mercury

Which planet experiences the greatest change between its actual day temperature and actual night temperature?

Mercury

When were the heat-trapping effects of gases that cause the greenhouse effect first measured by scientists?

More than 150 years ago.

According to scientists, the naturally occurring greenhouse effect makes Earth about 31∘C warmer than it would be if there were no greenhouse gases in our atmosphere. How do scientists "know" what Earth's temperature would be without greenhouse gases?

They calculate this temperature from Earth's reflectivity and distance from the Sun.

Which of the following is the most basic definition of a greenhouse gas?

a gas that absorbs infrared light

The strength of the Coriolis effect depends on

a planet's size and rotation rate.

On the graphs shown, you can identify an ice age by looking for __________.

a trough (bottom of a dip) on the temperature graph

Greenhouse gases in the atmosphere, such as carbon dioxide and water vapor, make Earth warmer than it would be otherwise because these gases __________.

absorb infrared light emitted by the surface

The thermosphere is warm because it

absorbs X rays.

Scientists have confidence in the predictions of today's best climate models because they __________.

agree well with actual data for recent decades