APEX APES 9.2.6 Read (Withgott 7th Edition) Global Climate Change

global climate change

The array of changes in aspects of Earth's climate, such as temperature, precipitation, and storm frequency and intensity.

global warming

An increase in Earth's average surface temperature.

greenhouse gas

A gas that absorbs infrared radiation released by Earth's surface and then warms the surface and troposphere by re-emitting infrared radiation, thus giving rise to the greenhouse effect.

greenhouse effect

The warming of Earth's surface and atmosphere (especially the troposphere) caused by the energy absorbed and re-emitted by greenhouse gases.

aerosols

Very fine liquid droplets or solid particles aloft in the atmosphere.

radiative forcing

The amount of change (positive or negative) in thermal energy that a factor (such as a greenhouse gas or an aerosol) causes in influencing Earth's temperature.

Milankovitch cyclesO

ne of three types of variations in Earth's rotation and orbit around the Sun that result in slight changes in the relative amounts of solar radiation reaching Earth's surface at different latitudes.

paleoclimate

Climate in the geologic past.

proxy indicatorA

source of indirect evidence that serves as a proxy, or substitute, for direct measurement and that sheds light on past climate.

climate model

A computer program that simulates dynamic climate processes by combining what is known about weather patterns, atmospheric circulation, atmosphere?ocean interactions, and feedback cycles.

Intergovernmental Panel on Climate Change (IPCC)

An international panel of climate scientists and government officials established in 1988 by the United Nations Environment Programme and the World Meteorological Organization.

ocean acidification

The process by which today's oceans are becoming more acidic (attaining lower pH) because of increased carbon dioxide concentrations in the atmosphere.

mitigation

The pursuit of strategies to lessen the severity of climate change, notably by reducing emissions of greenhouse gases.

adaptation

The pursuit of strategies to protect ourselves from the impacts of climate change.

carbon capture and storage

Technologies or approaches that seek to mitigate global climate change by removing carbon dioxide from power-plant or other emissions and trapping, or storing, the carbon dioxide underground, under pressure and in locations where it will not seep out, such as deep salt mines or depleted oil and gas deposits.

cap-and-trade system

A permit-trading system in which a government determines an acceptable level of pollution and then issues polluting parties permits to pollute. A company receives credit for amounts it does not emit and can then sell this credit to other companies.

United Nations Framework Convention on Climate Change

An international treaty signed in 1992 to promote international peace and cooperation in solving international economic, social, cultural, and humanitarian problems.

Kyoto Protocol

An international agreement drafted in 1997 that called for reducing, by 2012, emissions of six greenhouse gases to levels lower than their levels in 1990. It has been extended to 2020 until a replacement treaty can be reached.

carbon pricing

Strategies intended to compensate the public for the external costs of fossil fuel emissions and climate change, such as economic losses that result from impacts of climate change on property, health, and infrastructure.

carbon trading

A system in which permits for emitting carbon dioxide are traded from an entity that has low emissions to an entity with higher emissions.

carbon tax

A fee charged to entities that pollute by emitting carbon dioxide.

fee-and-dividend

A program of carbon taxes in which proceeds from the taxes are paid to consumers as a tax refund, or "dividend."

carbon offset

A voluntary payment to another entity, intended to enable that entity to reduce the greenhouse gas emissions that one is unable or unwilling to reduce oneself.

carbon neutrality

The state in which an individual, business, or institution emits no net carbon into the atmosphere.

geoengineering

Any of a suite of proposed efforts to cool Earth's climate by removing carbon dioxide from the atmosphere or reflecting sunlight away from Earth's surface.

carbon footprint

The cumulative amount of carbon, or carbon dioxide, that a person or institution emits, or is indirectly responsible for emitting, into the atmosphere.

What is the difference between global climate change and global warming?

What three factors influence climate?

Three natural factors that influence climate are the Sun, the atmosphere, and oceans.

What is a greenhouse gas, and what are some examples?

A greenhouse gas is a gas that absorbs infrared radiation released by Earth's surface and then warms the surface and troposphere by re-emitting energy, thus giving rise to the greenhouse effect. Some examples are water vapor, ozone, carbon dioxide, nitrous oxide, methane, and halocarbons.

Why does carbon dioxide, which does not trap heat as well as other greenhouse gases, contribute so much to the greenhouse effect?

Carbon dioxide is far more abundant in the atmosphere than other greenhouse gases.

What are two reasons that carbon dioxide gas concentrations in the atmosphere are rising so quickly?

Over the past two centuries, humans have extracted fossil fuels from the lithosphere and burned them, which has moved large amounts of carbon from the lithosphere to the atmosphere. People have also cleared forest land, which has removed trees that carry out photosynthesis and remove carbon dioxide from the atmosphere.

What is radiative forcing, and how does it compare for carbon dioxide and aerosols?

Radiative forcing is the amount of change in thermal energy that a factor (such as a greenhouse gas or an aerosol) causes in influencing Earth's temperature. Carbon dioxide exerts positive radiative forcing, which means that the gas has a warming effect on Earth. Aerosols exert negative radiative forcing, which means they have a cooling effect.

What are Milankovitch cycles?

Milankovitch cycles are one of three types of variations in Earth's rotation and orbit around the Sun that result in slight changes in the relative amounts of solar radiation reaching Earth's surface at different latitudes.

Why can't variations in solar output explain current changes in global climate?

Solar radiation has been decreasing since the 1970s and thus cannot explain global warming.

What trend can be seen in ocean absorption of carbon dioxide, and what effect is this trend having on global warming?

The oceans are absorbing less carbon dioxide than humans are adding to the atmosphere, so ocean absorption is slowing global warming but not preventing it.

What is paleoclimate, and how do scientists study it?

Paleoclimate is climate in the geologic past. Scientists learn about paleoclimate by studying core samples from ice caps, ice sheets, and glaciers. They also look at tree rings, packrat middens, and corals.

What are some direct measurements that scientists take of Earth's present-day climate?

Direct measurements of climate include measurements of temperature, rainfall, wind speed, air pressure, and concentrations of chemicals in the atmosphere and ocean.

What is the IPCC, and what does it do?

How have average surface temperatures on Earth changed in the last 100 years?

They have risen by about 1.1°C (2.0°F).

What does the IPCC predict global temperatures to be at the end of the 21st century?

Depending on how well we control emissions, the IPCC predicts global temperatures to be 1.0 - 3.7°C (1.8 - 6.7°F) higher than today's.

How has weather changed with global climate change?

Precipitation patterns have changed such that some regions receive less rain and experience drought, while other regions receive more rain and experience flooding. There is more extreme weather, such as droughts, floods, tornadoes, hurricanes, snowstorms, and heat waves.

What have been the effects of melting snow cover, glaciers, ice sheets, sea ice, and permafrost because of global warming?

Melting snow cover has changed the availability of meltwater during the summer in some areas. Melting ice sheets and sea ice have increased Earth's albedo, reducing the amount of energy reflected and causing further warming. Melting ice has also caused sea levels to rise. When permafrost thaws, it destabilizes ground that supports buildings and infrastructure.

What are two reasons that sea levels are rising?

Sea levels are rising because when ice at the poles and within mountain glaciers melts, it releases water into oceans. Also, sea levels are rising because water expands when it warms.

What two factors associated with climate change have an impact on corals?

Corals are affected by the temperature increase of ocean water, which leads to coral bleaching, and by the acidification of ocean water as more carbon dioxide dissolves in it.

What have been the effects of global climate change on organisms?

Many kinds of plants are experiencing earlier leafing-out times, which affects animal species that depend on them. Insects are also hatching earlier, birds are migrating earlier, and animals are breeding earlier. Many species are also shifting their geographic range.

What have been the effects of global climate change on society?

Extreme weather events associated with global warming have caused human deaths and damage to people's livelihoods. Crop yields are expected to increase to a point but then decline with further global warming. In some areas, growing seasons may shorten or be susceptible to drought. Human health problems are expected to increase as climate change causes increases in air pollution, expansion of tropical diseases borne by mosquitoes, and increases in injuries and diseases associated with extreme weather such as flooding.

What is the difference between mitigation and adaptation?

Mitigation is the pursuit of strategies to lessen the severity of climate change, while adaptation is pursuit of strategies to protect ourselves from the impacts of climate change.

What was the plan proposed by the United Nations Framework Convention on Climate Change, and was it successful?

The plan of the United Nations Framework Convention on Climate Change was to reduce greenhouse gas emissions to 1990 levels by 2000. It was not successful, because compliance was only voluntary, and emissions continued to rise.

What was the Kyoto Protocol, and what did it do?

The Kyoto Protocol was an international agreement drafted in 1997 that called for reducing, by 2012, emissions of six greenhouse gases to levels lower than their levels in 1990. Nations that signed the protocol decreased their emissions to 10.6% below their 1990 levels, but most of that reduction was due to the contraction of the economies of Russia and other nations of the former Soviet Bloc. The remaining nations experienced a 1.9% increase in emissions, while nations that were not part of the agreement (China, India, and the United States) also increased their emissions.

What is a cap-and-trade system, and has the United States implemented one?

A cap-and-trade system is a permit-trading system in which government determines an acceptable level of pollution and then issues polluting parties permits to pollute. Such a system was approved by the House of Representatives in 2009 but was not approved by the Senate, so responsibility for reducing emissions was passed to the Environmental Protection Agency, which began developing regulations.

What are carbon offsets and carbon neutrality, and how are they related?

Carbon offsets are voluntary payments to another entity, intended to enable that entity to reduce the greenhouse gas emissions that one is unable or unwilling to reduce oneself, whereas carbon neutrality is the condition in which no net carbon is emitted. Carbon offsets are popular with utilities, businesses, universities, and individuals who are aiming to achieve carbon neutrality.

What is geoengineering, and why is it controversial?

Geoengineering is any of a suite of proposed efforts to cool Earth's climate by removing carbon dioxide from the atmosphere or reflecting sunlight away from Earth's surface. It is controversial because the technology can take years to develop, could pose unforeseen risks, and takes incentives away from reducing emissions.