Environmental Science for AP - FR Ch 19 Climate Change

Global Change

Planetary scale changes in earth systems - Rising sea levels, increased extraction of fossil fuels, increased contamination, altered biogeochemical cycles, decreased biodiversity, emerging infectious diseases, overharvesting and exploitation of species

Global Climate Change

Changes in the average weather that occurs over an extended period of time - storm intensity, altered patterns of precipitation and temperature, altered patterns of ocean circulation

Global Warming

Increase in average temperature of earth over time - increase in heat waves

Greenhouse Warming Potential

Estimates how much a molecule of any compound can contribute to global warming over 100 years compared to a molecule of CO2

Greenhouse Effect

the process by which radiation from a planet's atmosphere warms the planet's surface

Greenhouse Gases

A gas in Earth's atmosphere that traps heat near the surface

Chlorofluorocarbons(CFCs)

Powerful greenhouse gas - emitted by refrigerators and aerosols - now a banned substance due to contributing to Ozone Layer Hole

Hydrochlorofluorocarbons(HCFCs)

A compound used in place of CFCs as it is less destrucive to ozone layer

Methane (CH4)

Powerful greenhouse gas (25x more powerful than CO2) - emitted by livestock, landfills, decomposition

Nitrous Oxide (N2O)

Greenhouse gas - sources: denitrification and fertilizers

Soil Sequestration

When carbon is absorbed by soils and is stored there for the long term

Water Vapor

Most common greenhouse gas - source: evaporation or transpiration of water - absorbs more IR than anything else, but does not persist in the atmosphere for long

How much radiation is reflected back into space by the Earth's surfaces?

1/3

What is the most common greenhouse gas?

Water vapor

What greenhouse gas has the greatest global warming potential?

CFCs

Which greenhouse gas has the biggest effect and why?

CO2 - largest concentration in the atmosphere

What are the largest and second largest natural sources of methane?

Wetlands (first), termites (second)

What agricultural practices result in greenhouse gases?

irrigation (methane), fertilizers (nitrogen), livestock (methane), manure (CO2 + Methane)

Greatest producers of methane in order of greatest to least

Livestock digestion, landfills, natural gas/petroleum

Greatest producer of nitrous oxides

Agricultural soils

Greatest producers of carbon dioxide

fossil fuels (for energy), fossil fuels (not for energy)

Natural sources of greenhouse gases

volcanoes, decomposition and digestion, denitrification, evaporation and transpiration

Anthropogenic sources of greenhouse gases

burning of fossil fuels, agriculture, deforestation, landfills, and industrial production of chemicals

Intergovernmental Panel on Climate Change (IPCC)

A scientific body under the UN, dedicated to the task of providing the world with an objective and view on climate change

Who observed that atmospheric CO2 concentrations varied seasonly and are rising overall over time?

Charles Keeling

Keeling Curve

a graph which plots the ongoing change in concentration of carbon dioxide in Earth's atmosphere since 1958 - data recorded at Mauna Loa, Hawaii

Evidence for climate change

Increasing CO2, increasing temperatures, changing species composition, proxy indicators

proxy indicators of climate change

indirect evidence that serve as substitutes for direct measurements of past climate -ice core samples, ancient pollen spores from lake sediments, tree rings, foraminafera, coral growth rings

Global tempature rise since 1880

1.4 F or .8 C

Foraminifera

Tiny marine organisms whose shells do not decay after death, which allows scientists to gain insight (proxy indicator) on ancient water temperatures - due to their preference for different water temps

Ice Cores

Deep pockets of ice that are studied due to the air bubbles present inside them that contain the atmospheric conditions of ancient eras

tree rings

tree growth is influenced by climate conditions, patterns in tree rings and isotopic composition within each ring reflect variations in past climate

Ancient pollen from lake sediments

proxy indicator for past climate - tells what kind of trees lived in an area in the past and thus types of temps/precip as well

Cause of temperature/CO2 shifts before humans

path of Earth's orbit/position relative to sun, orbital tilt

climate models

programs that combine what is known about atmospheric circulation, ocean circulation, atmosphere-ocean interactions, and feedback cycles to simulate climate processes and make predictions for the future

Effects of climate change

rising sea level, changing weather patterns, increased floods or droughts, destruction of crops, melting ice caps/glaciers, human health problems, ocean acidification

polar ice and glaciers melting

Arctic ice melting affects polar bear survival.

Food sources are dwindling for human Arctic dwellers.

Loss of freshwater supply - glaciers

Positive feedback loop in the arctic - less albedo - more absorption

permafrost melting

Results in erosion and loss of structural support, organic matter decomposes so significant amounts of methane and carbon dioxide will be released into the atmosphere - positive feedback loop

ocean acidification

when CO2 dissolves in seawater, it reacts with water to form carbonic acid, which lowers ocean pH - dissolves calcium carbonate shells of marine organisms

sea levels rise

Glaciers and ice caps melting and thermal expansion - freshwater resources contaminated, coastal communities need to relocate

climate change effects on organisms

ranges shifting towards poles, earlier migrating/blooming, coral bleaching, fragmentation of habitat prevents migration

Organisms ranges have shifted towards the poles

trying to find their optimal temperature conditions - mosquito and tick range increasing

coral bleaching

the loss of color in corals that occurs when stressed corals expel the algae that live in them

Future effects of climate change

heat waves

cold spells

precipitation patterns

storm intensity

ocean currents

effects on humans

heat waves

extended periods of above-normal temperatures - rise in energy demand - risk of death to poor and elderly - damage to crops and increased need for irrigation

Cold spells

polar vortex normally traps freezing air - with arctic warming - this weakens and cold air moves south - expands range of pests - can have positive effects

changes in precipitation patterns

More droughts in some areas

More flooding in some areas - landslides, erosion

Fresh water availability

storm intensity increase

ocean currents

thermohaline circulation slows down - less warm water to coastal europe

future effects of climate change on humans

climate refugees - relocation

health: heat waves, infectious disease

tourism: snow, coral reefs

Kyoto Protocol

An international agreement to reduce global emissions of greenhouse gases from all industrialized countries (5.2% by 2012) - US did not ratify.

precautionary principle

a principle based on the belief that action should be taken against a plausible environmental hazard - reduce emission, sequester carbon

Carbon Sequestration

Approach that involves taking CO2 out of the atmosphere. Can store in agricultural soils or retired agricultural land.

Paris Climate Agreement (2015)

A pledge by over 150 countries to significantly decrease their carbon emissions by 2030 - keep warming within 2C above pre-industrial levels

carbon offset

a voluntary payment made to compensate for greenhouse gas emissions - falls short - needs oversight to make sure money accomplishes what it is intended for

Cap and Trade

Mechanism to reduce the emission of pollutants by establishing a market for emission permits - only works if the cap is lowered over time

carbon tax

a fee that the government charges polluters for each unit of greenhouse gas they emit - financial incentive to reduce emissions - polluters tend to pass costs on to customers

Solutions on an individual level

Efficient living, dietary changes, voting

Solutions for businesses

move to renewable energy, energy efficient

Solutions for cities

Bike lanes, public transport, green spaces or trees to reduce city temperatures, LED lights, sustainable water management (capture rain for reuse, permeable driveways, rain gardens), transition to renewable energy

Solutions for nations

Carbon capture, carbon storage, carbon taxes, incentives to change to renewables

Mitigation

Limiting greenhouse gas emissions to moderate global climate change