Weather and Climate Chapter 14

Describe two examples of how the warmer temperatures due to increased CO2 in the atmosphere may lead to positive feedback effects.

1. Warmer temperatures will result in more water evaporated. More water vapor in the atmosphere will increase the greenhouse effect. 2. Warmer temperatures will increase the melting of polar ice and snow. This will decrease the earth's albedo, allowing more solar radiation to be absorbed.

Sunspot activity tends to follow a cycle of roughly:

11 years

Past climate data measured with instruments extends back about:

200 years

What is the current axial tilt of the earth?

23.5 degrees

Astronomical causes of climate change occur with cycles of:

26,000 - 100,000 yrs.

Which of these is the most important cause of the increase in atmospheric CO2? A) decaying vegetation B) burning of coal and petroleum C) wetlands and swamps D) cattle E) deforestation

B) burning of coal and petroleum

Variations in the shape of the earth's orbit: A) have a cycle of about three million years. B) have a cycle of about 100,000 years. C) will eventually lead to the earth having a perfectly circular orbit. D) are related to changes in sunspot activity on the surface of the Sun.

B) have a cycle of about 100,000 years.

Which of the following gases may be contributing to a greenhouse warming? A) hydrogen B) methane C) nitrogen D) oxygen E) carbon monoxide

B) methane

Which association is NOT correct? A) obliquity — 41,000 years B) eccentricity — 100,000 years C) precession — 13,000 years

C) precession — 13,000 years

Global warming is obviously associated with temperature increases. List two additional effects that global warming may have upon Earth's climate.

Changes in precipitation patterns, changes in precipitation amounts, changes in frequency and severity of storms, changes in sea level, changes in paths of cyclonic storms.

Which of the following is a trace greenhouse gas? A) carbon B) carbon monoxide C) oxygen D) nitrous oxide

D) nitrous oxide

The acronym GCM stands for:

General Circulation Model

Who is credited with developing the modern theory that variations in the earth's orbit influence climate change?

Milutin Milankovitch

The person who first developed and strongly advocated the astronomical theory was:

Milutin Milankovitch.

What was the name of the volcano that erupted in 1991 in the Phillipines and lowered global temperatures by 0.5∘C?

Pinatuba

________ was the volcano that erupted in 1815 and is credited with causing "the year without a summer".

Tambora

The group assembled by the World Meteorological Organization for the purpose of assessing the known information related to human-induced climate change is known as:

The Intergovernmental Panel on Climate Change

Methane is naturally produced by bacteria in ________ environments.

anaerobic

In addition to sea level rise, oceans respond to increasing carbon dioxide in the atmosphere by:

becoming increasingly acidic

The type of aerosol that warms the atmosphere by absorbing solar radiation and increasing the surface albedo of snow and ice is called:

black carbon

List four greenhouse gases.

carbon dioxide, nitrogen oxide, methane, water vapor, CFCs

The eccentricity portion of Milankovitch's astronomical theory refers to:

changes in the shape of Earth's orbit.

In addition to their role in depleting stratospheric ozone, ________ are also effective greenhouse gases.

cholorfluorocarbons

You find an old tree stump in a forest and would like to use it for tree-ring analysis, but you don't know when the tree was cut down. The best way to establish dates for the analysis is to:

compare patterns in the tree rings to ring chronologies sampled from nearby trees on known dates.

When did the supercontinent Pangaea exist?

during the Paleozoic period

A positive-feedback mechanism tends to produce results that are opposite of the initial change and tend to offset it. (t/f)

false

CO2 concentrations today are not any higher than they have been during past high points over the last 400,000 years. (t/f)

false

Carbon dioxide gas is a strong absorber of solar radiation. (t/f)

false

Carbon dioxide is the only greenhouse gas that has displayed increasing concentrations over the last century. (t/f)

false

Global warming is not expected to involve changes in rainfall. (t/f)

false

It is believed that the temperature rise caused by increased atmospheric carbon dioxide will be greater in the tropics than in the polar regions. (t/f)

false

Most experts agree that the process of global warming can be reversed within a few years if there is sufficient global cooperation. (t/f)

false

Recent studies indicate that the impact on climate of a great explosive volcanic eruption can last for decades. (t/f)

false

Studies of ocean-floor sediments are of little use when studying long-term climate change. (t/f)

false

Studies of past climates have shown that climate has varied only on time scales of tens of thousands to millions of years. (t/f)

false

If the tilt of the earth's axis changes, how does this affect the temperature change across the seasons?

less tilt, smaller seasonal change

List two ways in which humans likely caused climate changes before the time of the industrial revolution.

overgrazing and fire

Large amounts of long-stored organic material will begin to decay and release carbon dioxide when extensive areas of:

permafrost thaws

The most likely explanation for evidence of glacial activity in places such as Africa and Australia is:

plate tectonics

Oxygen isotope analysis measures the:

proportion of 2 different types of oxygen atoms

Sea floor sediments provide useful climate data because they contain:

remains of living organisms

What term is used to describe the strategy used by scientists who are trying to predict the differing outcomes for a wide range of possible assumptions?

scenarios

The ________ the tilt of the earth, the smaller the temperature difference between summer and winter.

smaller

The Milankovitch cycles cannot entirely explain recent global warming trends because:

they operate on a very long time scale and cannot address shorter term cycles.

What is the primary goal of a paleoclimatologist?

to reconstruct past climates

List four kinds of evidence that can provide data about past climates.

tree rings, soil layers, ice cores, ocean sediments, pollen, corals

According to glacial ice records, the Earth was significantly cooler between 10,000 and 40,000 years ago than it is today. (t/f)

true

Carbon dioxide is released to the atmosphere as vegetation decays. (t/f)

true

During periods when glaciers are extensive, the concentration of 18O in seawater increases. (t/f)

true

Long-term climate change evidence is in reasonable agreement with predictions from the astronomical theory. (t/f)

true

One possible result of the addition of carbon dioxide to the atmosphere is an increase in cloud cover which, in turn, could partly offset a global temperature increase. (t/f)

true

Recent studies based on the analysis of sea-floor sediments tend to support the astronomical theory. (t/f)

true

Recent years have been some of the warmest years measured. (t/f)

true

Since the 1970s, the mean global temperature has risen by about 0.6°C. (t/f)

true

Stronger and more numerous hurricanes have been predicted as a possible result of global warming. (t/f)

true

There are insufficient data to determine with a strong degree of certainty that solar variability affects climate. (t/f)

true

When glaciers are growing larger, the concentration of the heavier oxygen isotope in sea water increases. (t/f)

true

Compared to climate changes due to plate tectonics and astronomical causes, the changes due to volcanic eruptions are:

very short

Requirements for an ice age on Earth include: A) smaller obliquity angle. B) a weaker Sun. C) larger obliquity angle. D) continents located at high latitudes. E) continents located at low latitudes.

D) continents located at high latitudes.

Which of the following is NOT associated with the Milankovitch astronomical theory of climate change? A) precession B) eccentricity C) obliquity D) lunar phases

D) lunar phases

Which of the following is NOT a part of the climate system? A) hydrosphere B) lithosphere C) biosphere D) atmosphere E) climosphere

E) climosphere

If a volcanic eruption produces a climate impact that lasts for a year or longer, the most likely culprit is:

aerosols produced by sulfur dioxide emitted from the volcano.

In what way were humans influencing climate prior to the Industrial Revolution?

alteration of ground cover for grazing and agriculture

The continents have been in the exact same locations since the earth began. (t/f)

false

The smallest temperature increases due to global warming are expected in the middle latitudes. (t/f)

false

The tilt of the earth's axis varies between 22.1 and 28.5 degrees. (t/f)

false

El Chichon appears to have had a greater impact on atmospheric temperatures than did Mount St. Helens. (t/f)

true

Global warming may cause changes in Earth's albedo. (t/f)

true

Global warming will cause significant increases in sea level due to the thermal expansion of the ocean's waters. (t/f)

true

Increased cloudiness as a result of warmer temperatures could provide both positive and negative feedbacks in the climate system. (t/f)

true

A major part of the greenhouse effect is that it involves the absorption of the earth's outgoing radiation by atmospheric gases. Along with carbon dioxide, what atmospheric component is largely responsible for this process?

water vapor

The length of time that a volcanic eruption impacts the climate is largely determined by:

whether the ash or gas reaches the stratosphere

The term anaerobic means:

without oxygen

Which of the following is NOT a projected effect of global warming for the coming century? A) a decrease in the areas affected by drought B) increased risk of landslides and mudslides C) increased risk of avalanches D) increase in intense hurricane activity

A) a decrease in the areas affected by drought

Measured variations in the Sun's emission of radiation and observed changes in the earth's climate: A) have not been clearly linked. B) happen on an 11-year cycle. C) happen on a 22-year cycle. D) are well understood.

A) have not been clearly linked.

Plate tectonics (continental drift): A) may help us better understand the cause of the Ice Age. B) is probably responsible for some climatic changes that occur on a time scale of thousands of years. C) may be a key factor in explaining the cooling trend since the 1940s.

A) may help us better understand the cause of the Ice Age.

Volcanic eruptions can act as agents for climate change since they: A) increase the numbers of cyclones. B) increase the amount of evaporation. C) cause small changes in the earth's tilt. D) reduce the solar energy at Earth's surface. E) release large amounts of heat.

D) reduce the solar energy at Earth's surface.

Which one of the following statements is NOT related to the astronomical theory of climatic change? A) variations in the shape of the earth's orbit B) changes in the angle that the earth's axis makes with the plane of the ecliptic C) wobbling of the earth's axis D) variations in solar output E) distance variations between the earth and the Sun

D) variations in solar output

The climate system consists of the: A) cryosphere. B) atmosphere. C) hydrosphere. D) just the cryosphere and atmosphere. E) the cryosphere, atmosphere, hydrosphere, biosphere, and solid Earth.

E) the cryosphere, atmosphere, hydrosphere, biosphere, and solid Earth.

Why are the climate forecasts of GCMs not to be fully trusted?

Underlying assumptions influence the outcome and may not be totally accurate.

At what star does the North Pole point at the opposite extreme from its current position?

Vega

Corals can provide proxy data through the ________ that they extract from seawater while growing.

calcium carbonate

The combustion of coal and oil is a major source of which greenhouse gas?

carbon dioxide

The large plates that make up the outer portion of the earth move approximately a few ________ per year.

centimeters

The best way to estimate the cooling effect of a volcanic eruption is by estimating the total volume of material ejected. (t/f)

false

The combined influence of CFCs, methane and nitrous oxide as greenhouse gases is insignificant. (t/f)

false

Proxy data: A) provide climate data representing times when instruments were not available to measure them. B) are difficult to find because they occur only in very limited areas. C) come quality-controlled instrument records. D) can only extend the temperature record back an additional 500 years.

A) provide climate data representing times when instruments were not available to measure them.

Which of the following is a possible consequence of a greenhouse warming? A) sea-level rise B) increase in sea ice C) a decrease in global mean precipitation D) lower frequency of hurricanes

A) sea-level rise

Oxygen-isotope analysis is used on all of the following sources of proxy data EXCEPT: A) tree rings. B) coral reefs. C) glacial ice. D) sea floor sediments.

A) tree rings.

The sunspots produce huge ejections of particles that: A) rapidly increase the temperature at the surface of Earth. B) produce auroras in Earth's atmosphere. C) accelerate the melting of ice sheets. D) do not generally interact with the Earth system.

B) produce auroras in Earth's atmosphere

We have not yet established the impact of solar variability on the Earth's climate system because: A) we have no way of measuring solar variability directly. B) satellites have not yet been around long enough to provide a data set of adequate length. C) most scientists now agree that solar output is constant and does not vary. D) it is not a legitimate enough theory to gain much attention from the scientific community.

B) satellites have not yet been around long enough to provide a data set of adequate length.

It is likely that an increase in global temperature would result in an increase in cloud cover. Which of the following statements BEST describes the total impact of additional clouds on the Earth system? A) Clouds provide an exclusively negative-feedback response to warming. B) Clouds provide an exclusively positive-feedback response to warming. C) Clouds provide both positive-feedback and negative-feedback responses to warming. D) Clouds provide neither positive-feedback nor negative feedback responses to warming.

C) Clouds provide both positive-feedback and negative-feedback responses to warming.

Warming temperatures melt ice cover, exposing a darker surface that absorbs more solar radiation. In response, the air warms even further. This is an example of: A) a stable-feedback mechanism. B) a negative feedback mechanism. C) a positive feedback mechanism. D) a variable-feedback mechanism.

C) a positive feedback mechanism.

Which of the following is NOT a greenhouse gas? A) methane B) CFCs C) argon D) carbon dioxide

C) argon

Sulfur dioxide aerosols: A) lower cloud albedo. B) are rarely emitted during volcanic eruptions. C) can serve as condensation nuclei. D) do not exist in reality.

C) can serve as condensation nuclei.

Scientists expect climate change to: A) cause every place on the planet to warm evenly and consistently. B) cause each year to be consecutively warmer than the one before. C) cause each decade to be warmer than the previous one. D) cause some areas on the planet to cool dramatically.

C) cause each decade to be warmer than the previous one.

The atmosphere's CO2 content is rising. Which one of the following is a significant contributor to this increase? A) refrigerant leakage B) rice paddies C) deforestation D) aerosol spray cans

C) deforestation

Studies have shown that the sea level: A) should drop over the next 100 years. B) should not change significantly over the next 100 years. C) has risen about 25 centimeters since 1870. D) has not changed measurably over the last century.

C) has risen about 25 centimeters since 1870.

Oxygen-isotope analysis: A) has been shown to be of little or no use in the study of past climatic changes. B) cannot be carried out on ice cores or sea floor sediments, but works well for tree ring analysis. C) relies on the fact that 16O evaporates from the ocean more readily than 18O. D) is very simple.

C) relies on the fact that 16O evaporates from the ocean more readily than 18O.

One source of oxygen isotope measurements used for climate reconstruction come from: A) air pollution. B) cores from old trees. C) sea floor sediments. D) packrat middens.

C) sea floor sediments.

In comparison to the global average, warming in the polar regions could be: A) about the same. B) about 50% lower. C) two to three times greater. D) ten times greater.

C) two to three times greater.

The cryosphere consists of:

ice and snow

The volcano that caused "the year without a summer" was:

tambora

What property of glacial ice helps climatologists to reconstruct the CO2 concentrations of the atmosphere during the past?

the contents of air bubbles trapped in ice

Which regions on Earth have displayed the greatest temperature anomalies in 2010 (based on the 1951-1980 average)?

the high latitudes

The part of a plant that is best preserved and can most easily be used for climate reconstruction is:

the pollen

Why is the idea of plate tectonics only considered for climate changes that occur over very long periods?

the rate of plate movement is very slow