Anthropogenic activités such as _______ and ______ have major effects on global climates.
Fossil fuel combustion, deforestation
Global Change Examples
rising sea levels, increased extraction of fossil fuels, increased contamination, altered biogeochemical cycles, decreased biodiversity, emerging infectious diseases, over harvesting/ exploitation of plants and animals
Global climate change Examples
increased storm intensity, altered patterns of precipitation and temperature, altered patterns of ocean circulation
Global warming examples
the warming of the planet'e land, air, and water, increased heat waves, reduced cold spells
Things that make our planet warm:
solar radiation and greenhouse gases
The Sun-Earth Heating System:
-ultimate source of most energy on earth -Sun emits solar radiation that strikes earth -Planet warms and emits radiation back toward atmosphere -Sun radiation energy: high energy visible radiation and ultraviolet radiation -Earth radiation energy: infrared radiation -this difference in radiation causes the planet to warm
Does infrared radiation pass easily through the atmosphere?
NO but ultraviolet and visible radiation do
What is the net flux of energy in the sun-earth heating system?
Are the fluctuations in input/output of energy from the sun-earth heating system short or long term?
Short term, influenced by changes in incoming solar radiation from increased solar activity and changes in outgoing radiation from an increase in atmospheric gases that absorb infrared radiation.
What happens if incoming solar energy is greater than the sum of reflected solar energy and radiated infrared energy from earth?
Energy accumulates faster than it is dispersed and the planet becomes warmer.
What happens if incoming solar energy is less than the sum of the two outputs?
the planet becomes cooler----these changes in inputs and outputs cause natural temperature change over time
Most common gases in the atmosphere?
N2 and O2 (99% of the atmosphere). They do not absorb infrared radiation and are not greenhouse gases and do not contribute to the warming of earth
Greenhouse gases make up a very large or small portion of the atmosphere?
Small. Most common is Water vapor (H2O). It absorbs more infrared radiation more than any ofter compound but it has a short lifespan. Other greenhouse gases are Carbon Dioxide (CO2), Methane (CH4), nitrous oxide (N2o) and Ozone (O3)
Is ozone in the stratosphere beneficial?
yes it filters out harmful ultraviolet radiation
What does ozone in the lower troposphere do
acts as a greenhouse gas and can cause increased warming of earth also it is an air pollutant causing damage to plants and human respiratory systems
What type of greenhouse gas does not exist naturally?
Chlorofluorocarbons (CFCs). They occur in atmosphere exclusively due to production by humans and have caused hole in ozone layer
What is the main concern with greenhouse Gases?
that human activities have increased them to an unnatural ammount
The contribution of each gas to global warming depends in part on its ___
Greenhouse warming potential. To calculate this, scientists consider the amount of infrered energy that a given gas can absorb and how long the molecule of gas can persist in the atmosphere
Which has a lower warming potential water vapor of carbon dioxide?
Effect of each greenhouse gas depends on both ___
its warming potential and its concentration in the atmosphere
What is the greatest contributor to the greenhouse effect?
Carbon dioxide. It has the highest concentration
Increasing the concentration of any historically present greenhouse gas should cause?
more infrared radiation to be absorbed in the atmosphere, which will then radiate more energy back toward the surface of the planet and cause the planet to warm
Natural sources of greenhouse gases include:
volcanic eruptions, decomposition, digestion, denitrification, evaporation, and evapotranspiration
What do volcanic eruptions release?
significant amounts of Carbon dioxide on the geologic time scale, and ash (reflection incoming solar radiation back to space for a cooling effect) but effects are short term
What does Decomposition release?
dead organic matter is ultimately converted into carbon dioxide. Methane is created where there is not enough oxygen available to produce carbon dioxide (wetlands)
What does digestion release?
methane (termites are second largest source of methane)
What does denitrification release?
Nitrous oxide (N2O) occurs in wetlands where it enters atmosphere as greenhouse gas
What do evaporation and Evapotranspiration release?
Water vapor is most abundant and greatest natural contributor to global warming
What are some anthropogenic sources of Greenhouse Gases?
Burning of fossil fuels, agricultural practices, deforestation, landfills, and industrial production of new greenhouse chemicals
What does the burning of fossil fuels produce?
CO2 which goes into the atmosphere. The rate it is going into the atmosphere is much greater than the rate it is coming out. also in some cases can release methane and nitrous oxide
Fossils fuels that produce CO2 greatest to least
coal, oil, natural gas
What role does PM play in global warming?
it may reflect solar radiation under some conditions. it can lower albedo by absorbing more sun energy
What does agricultural practices release?
over irrigation: methane and nitrous oxide because of low oxygen environment Synthetic fertilizers, manures, and things that natural fix atmospheric nitrogen can create nitrous oxide Also livestock can produce methane Manure produces CO2 or methane
What does Deforestation release?
Trees remove CO2 naturally and deforestation can lead to a net increase in atmospheric CO2 because mass of carbon that made up the trees is added to the atmosphere by combustion or decomposition
What does landfills release?
methane by product
What does the industrial production of new greenhouse chemicals release?
CFC's. Also hydrochloroflurocarbons (HCFCs). Production of CFCs was phased out by Montreal Protocol and developed countries will phase out HCFCs by 2030
Biggest producers of methane
Energy production and combustion, livestock digestion, landfills
Biggest producers of Nitrous oxide
Biggest producer of carbon dioxide
Combustion to generate electricity, combustion for transportation, industrial processes
Intergovernmental Panel on Climate Change to assess climate change
Charles David Keeling was?
collected data throughout the year on CO2 (different than other scientists) and found that the levels varied seasonally and concentration increased from year to year. this increase over time is correlated to increased human emissions.
What causes seasonal variation of CO2?
In spring plants increase absorption of CO2 to carry out photosynthesis. In fall, leaves drop and stuff so uptake of CO2 by plants declines and increases in atmosphere
Highest millions of metric tons of CO2:
China, United States
Highest per capita metric tons of CO2:
United States, Australia
Per capita consumption of fossil fuel and materials is greatest in _____________ countries.
How much did Global temperatures increase from 1880-2013? (shown on map made by NASA)
.8 degrees C, unevenly distributed too
How much of the Northern ice cap has melted?
45%, threatening polar bears and their ecosystem
What small fish is found in sediment and used to determine previous temperatures?
What is another way scientists can determine changes in greenhouse gas concentrations and temperature over time?
examining ancient ice (air bubbles)
Most of the observed increase in global average temperatures since the mid-twentieth century has been the result of?
Increased concentrations of anthropogenic greenhouse gases
leaves people w/out steady water supply
Melting of permafrost:
smaller lakes, human structure problems, composing organic matter
rise and water become warmer
Animals are affected by climate change:
seasonal habits, habitats, can't evolve fast enough
damage to humans, crops
damage to humans, crops
unpredictibility and also effects to the land
unpredictable and devastating
Ocean current shift:
distribution of heat on planet disrupted, thermohaline circulation
Effects on humans:
relocate, spread disease (malaria), more death related to temperature, economics effected,
Is the US in Kyoto Protocol?
When did EPA start regulating greenhouse gases?
Globally, greenhouse gases increased by __% between 1990 and 2013