Chapter 11 (Climate: How Does Global Climate Change?)
Facts about precipitation effects of climate change:
-There's been an increase in frequency and intensity of heavy downpours in the United States over the past 3-5 decades.
Earth's climate is in a period of global warming caused by human activities such as increased industrialization which has resulted in what 4 things?
1) Increased greenhouse gas release 2)Increased global temperatures 3)Increased glacial melting 4) Resulted in rising sea levels
How much is the sea level expected to rise?
1-4 feet
What is a feedback loop?
A loop in a system that responds to and produces changes in levels of stocks that either amplify or counter a change. Scientists are applying this to climate change.
What happens when radiation is directed downward toward the Earth's surface?
A warming effect is created.
Small island nations such as the Maldives are in the international spotlight because they: A) May be among the first nations to be completely flooded by rising sea levels B) Are accepting climate change refugees from other nations C) Are the largest emissions producers in their respective areas D) Have exceeded the emissions reductions set by the Kyoto Protocol
A) May be among the first nations to be completely flooded by rising sea levels
Which of the following may result in a positive feedback mechanism that would intensify climate change effects? A) Warmer temperatures result in thermal expansion, leading to sea level rise B) At higher temperatures, trees increase rates of photosynthesis C) A large volcano emits huge quantities of sulfate aerosols into the atmosphere D) An increase in rainfall results in increased plant growth E) None of the above
A) Warmer temperatures result in thermal expansion, leading to sea level rise.
What will droughts affect?
Affect regional agricultural yields and wildfires in the (south) west
Greenhouse Effect
Any system where there's a greater inflow of energy and trapping of heat when compared to the amount of heat that escapes. Some energy from the sun is trapped at the Earth's surface while some of this energy radiates back into space. A small scale greenhouse effect: when you park your car in the sun with the windows shut on a hot day, this is a warming system caused by a small scale greenhouse effect.
What is C02's natural atmospheric life and purpose.
Atmospheric life: 50-200 years Purpose: Maintain a balance between oceans and atmosphere
What is the cause of ocean acidification?
Increasing CO2 has resulted in a 30% increase in acidity.
How was reliable data collected prior to the instrumental period?
By drilling bores deep into Earth's crust.
What is the most significant greenhouse gas?
CO2
Global Climate
Climate is the average weather conditions over a significant period of time for a particular region of Earth, but global climate is when we examine the long-term trends in these conditions for the planet as a whole.
Clicker Q1: An example of proxies used to help understand past climates would be: A) Direct records of regional temperatures B) Current levels of CO2 in the atmosphere C) Current measurements of solar radiation D) Ancient sediments of past glacial activity E) None of the above
D) Ancient sediments of past glacial activity
Human source of methane in the atmosphere include which of the following? A) Livestock production B) Rice farming C) Wetlands D) Coal Mining E) All of the above
E) All of the above
What are halocarbons (ghg)?
Halocarbons have no natural source, but are synthesized for use as aerosol spray, refrigerants, solvents, and fire retardants. They stay in the atmosphere for 15-180 years.
How much has the atmospheric concentration of CO2 gone up per year? What about the current levels?
It's gone up .05% per year since 1958. Current levels of atmospheric CO2 are 400 parts per million--super super high.
What increases the albedo (reflectivity) effect?
Light colored surfaces
Along with collecting surface air temperatures (SAT), scientists also collect MAT and SST. What do these stand for?
MAT: Average Marine Air Temperatures SST: Sea-Surface Water Temperatures
What is the primary contributor to sea-level rise?
Melting of ice sheets
How does methane accumulate?
Methane accumulates as a GHG after being released from coal mines, natural gas leaks, rice farming, livestock production, and landfills.
Methan is a ghg. What does it do and what is the current methane concentration?
Methane traps heat 21 times more effectively than CO2. Methane concentrations are 250% greater than before the industrial revolution.
Proxy
Observable and measurable phenomena that serve as indirect indicators of climate changes. Ex: tree rings can tell us about the climate in the past.
Most of the Earth is covered by __
Oceans
Difference between positive and negative feedback
Pos. Feedback: Enhances the original change Neg. Feedback: Counters the original change
Nitrous Oxides (N2) (ghg)
Produced from industrial processes that produce nylon and from fossil fuel combustion. Atmospheric lifetime: 120 years and traps heat 310 times more effectively than CO2
Geothermal Gradient
Temperature increases with depth in the Earth's crust due to decaying radioactive elements that release energy and heat the crust. Temperature changes on the surface affect geothermal gradients and provide historical data.
What is the IPCC?
The IPCC is the Intergovernmental Panel on Climate Change and they report on climate change every 5 years. They determined that human activity has been the leading cause of climate change since 1950.
Instrumental Period
The current era in which we have temperature records for Earth's surface air temperature that are based on readings taken directly with instruments such as thermometers. This period improved data accuracy.
What is thermal expansion?
The expansion of something as it warms; particularly, when water warms the expansion will raise the sea level.
Albedo
The reflectivity of a surface.
2 examples of green house gases (ghgs) and what they do.
Two examples: water vapor + carbon dioxide What they do: They redirect heat rising from Earth's surface back down to the surface.