Final Review

Our planet earth

http://www.youtube.com/watch?v=6D5FwFSOJf8

The earth’s climate systemAtmosphere

Land

Ocean

Sea ice

Problem I: Different parts of the world are strongly connected to each other (The “Teleconnection Problem”)

Problem II: Different components of the earth system (atmosphere, land, ocean, ice,

clouds, etc) are strongly interacting with each other

(The “Feedback Problem”)

Problem III: The global climate models divide the earth into many small pixels (called grids), but the earth

system composes of both very big objects (such as the whole Pacific Ocean) and very small objects (such as the cloud droplets), making it very difficult to draw

them on the same page (The “Subgrid-Scale Problem”)

AstronomyMeteorologyAgriculture

FoodWeather

CommunicationTransportationEngineeringMaterialsEnergy

EnvironmentHealth

ComputerMechanicsChemistryPhysics Math

Earth SciBiology

0 500 1500 20001000500BC

Human Needs

Science

Middle Ages

Archimedes

Socrates Galileo

BrunoMadam Curie

Einstein

Time

Spirit of Independent Thinking

Individual Objects

(Analysis)

Organic System

(Synthesis)

Corot: Ville D'avray (1865-70)

Jin Nong (金农 ): Moon river (1687-1764)

Tianxin Zhang (张天新）

RadiationCloud/precipitation

Shallow convection Boundary layer turbulence

Mesoscale convective system ThunderstormTornado

Heat waveMidlatitude cycloneAtmospheric riverTropical cyclone

Diurnal variation

Madden-Julian Oscillation Tropical wavesAnnular modes

100,000yr100yr10yr1yr1mon1day1min1sec10-15sec

Global Climate System

Globe

Continent

State

City

Football field

1 mm

1 m

Spatial Scale

Time Scale

10-4 m Composition

Monsoon

ENSOQBO

Global warmingMulti-decadal Oscillation

Ice ageGlacial cycleAbrupt change

The most common atmospheric circulation

structure

L

H

H

L

HeatingCoolingor No Heating

Imbalance of heating Imbalance of temperature Imbalance of pressure Wind

Three-Cell Model

Hadley Cell (thermal): Heating in tropics forms surface low and upper level high air converges equatorward at surface, rises, and diverges poleward aloft descends in the subtropics

Ferrel Cell (dynamical): Dynamical response to Hadley and polar cells

Polar Cell (thermal): Driven by heating at 50 degree latitude and cooling at the poles

Tropical Walker Circulation andEl Nino/Southern Oscillation

(ENSO)

• Southern Oscillation: The atmospheric oscillation associated with the El Nino-La Nina cycle.

• The whole phenomena is now called El Nino/Southern Oscillation (ENSO)

• El Nino: Very warm sea surface temperature over central and eastern tropical Pacific, which occurs every 3-7 years. The Walker Circulation becomes disrupted during El Niño events, which weakens upwelling in eastern Pacific.

• La Nina: the opposite condition to El Nino

• A seasonal reversal of wind due to seasonal thermal differences between landmasses and large water bodies

• Orographic lifting often enhances precipitation totals

The Seasonal “Monsoon”

Tropical cyclones (Hurricanes)

Supercell thunderstorm and tornado

L

H

Video: Save our planet

“I don't understand why when we destroy something created by man, we call it "vandalism” but when we destroy something created by nature, we call it progress..” -- by one youtube viewer

The most common atmospheric circulation structure

L

H

H

L

HeatingCoolingor No Heating

Imbalance of heating Imbalance of temperature Imbalance of pressure Wind

Radiation Convection Conduction

Latent/Sensible

BiosphereLand/Ocean/Ice/

Stratosphere Feedback

Greenhouse Gases

Pollution

Clouds Precipitation (Latent heat)

SpiritualSocialHealthEconomy

Global connections

Global map of deferestation

Global distribution of PM2.5

Image from NASA Credit: Dalhousie University, Aaron van Donkelaar

Observed change of greenhouse gases

Global atmospheric concentrations of CO2 and CH4 have increased markedly as a result of human activities since 1750 and now far exceed pre-industrial values determined from ice core measurements spanning the last 650,000 years!

Greenhouse gas emissions per capita

The developed countries and developing countries contribute almost equally to the emissions of GHGs.

Green economy

All the ancient civilizations emphasized being in harmony with

nature• Ancient Greece: Pythagoras• Ancient China: Lao Tzu, Taoism• Ancient India: various • Ancient Babylonian and Egypt: All things

are the result of organic evolution