GLOBAL CLIMATE CHANGEForces of nature

Climate data information UCAR

Radiative Forcing (+) or (-)External Forces

OrInternal Forces

Climate Change

Cooling (Reflecting sunlight)

Warming(Greenhouse effect)

Global Warming1. Natural

1. U.V. Radiation2. Natural Cycles

1. Milankivitch2. Solar spots

3. GHG 1. CO2, H2O, CH4, 03, N2O

2. Anthropogenic1. Increase in GHG

Climates have changed through history

Proxy evidence: Early atmosphere :CH4, N2O, CO2 Increase in plants decreased CO2 levels pla

net cooled off Yet warm enough to have palm trees at the

poles Vostok Ice core: Supports Milankovitch

cycles, gradual change Also showed rapid change, why? GOCB

Cold Salty water is more dense, Fresh water freezes faster, would stop GOCB,

Entered ocean from melting ice Change in CO2 levels has not been

explained, just correlation Past 150 years

19 of the 20 warmest years on record occurred since 1980

Vostok ice core

If fresh water is added to the marine water it becomes less dense and will not sinkThe combo water stalls the GOCBPlaces like Ireland will become much colder

Milankovitch cycles Eccentricity : Earth gets closer and farther away from the sun on 100,000 year intervals

Solar variability

Carbon dioxide and global climate

1895 Svante Arrhenius: predicted CO2 from coal combustion would increase global temps

Keeling curve Global surface temperatures don’t mat

ch atmosphere increases POD: Cooling of Ocean temperatures Increased volcanic action Reduction in O3

A series of small volcanoes since 2000 that have spewed sunlight-blocking ash skyward

The natural 11-year solar cycle, whose declining phase lasted longer than usual: from 2000 to 2009

Variations in the exchange of heat between the ocean and atmosphere

Keeling Curve

Oceans have been absorbing energy

POD event 10 yr cycle Since 2000 more

volcanic activity Aerosols Sulfates

Sun spots solar flares Less Energy from sun

Urban heat islands: Why do we care about Urban heat islands? Urban heat islands cause _________ which can lead to______Increased energy consumption: high peak demand and increased chance of blackouts or brownouts.

Increased demand in energy; greater greenhouse gas emissions; higher temperatures.

Increased demand in energy; greater emission in pollutants from power plants.; formation of ground-level ozone.Increased demand in energy , greater emission in pollutants from power plants; Compromised human health and comfort: Warmer days and nights, along with higher air pollution levels, can contribute to general discomfort, respiratory difficulties, heat cramps and exhaustion, non-fatal heat stroke, and heat-related mortality.Hot pavement and rooftop surfaces; the transfer their excess heat to stormwater, which then drains into storm sewers and raises water temperatures as it is released into streams, rivers, ponds, and lakes. Rapid temperature changes can be stressful to aquatic ecosystems. Impaired water quality:

Planetary Albedo1. Natural

a. Volcanoesb. Snow/Ice c. Clouds

2. Anthropogenica. Aerosols

i. dust ii. soot

POSITIVE FEEDBACK LOOP

Consequences of GCC GOCB will stall and lower global temperature Sea levels will rise and flood coastal areas Climates change

Arctic: permafrost is melting buildings and infrastructures are changing

Local cultures face extinction Seasons lengths will change

Summers longer increase in insect populations that carry disease

Cause a change in migration patterns, Change in growing patterns, animals will migrate

farter north

Effects of Global Climate Change Increase of

temperature 2.5-10°F by 2100 (IPCC)

Less snowpack in western U.S.

Increase in rain fed crop yield 5-20%,

More frequent and intense heat waves in cites that currently have them

Benefits of green roofs Reduced energy use:  Reduced air pollution and greenhouse gas

emissions:  Improved human health and comfort:  Enhanced stormwater management and

water quality:  Improved quality of life: 

Proposed solutions Kyoto protocol Cap and Trade Voluntary limits