Climate Change: An Inter-disciplinary Approach to Problem Solving (AOSS 480 // NRE 480) Richard B. Rood Cell: 301-526-8572 2525 Space Research Building.

Climate Change: An Inter-disciplinary Approach to Problem Solving

(AOSS 480 // NRE 480)

Richard B. RoodCell: 301-526-8572

2525 Space Research Building (North Campus)[email protected]

http://aoss.engin.umich.edu/people/rbrood

Winter 2015February 5, 2015

Class Information and News

• Ctools site: AOSS_SNRE_480_001_W15

– Record of course

• Rood’s Class MediaWiki Site– http://climateknowledge.org/classes/index.php/Climate_Change:_The_Move_to_Action

• A tumbler site to help me remember– http://openclimate.tumblr.com/

Resources and Recommended Reading

• Rood’s Series on Bumps and Wiggles

• Past, Present and Future of Atlantic Meridional Overturning Circulation, Srokosz et al., BAMS, 2012

Outline: Class 9, Winter 2015

• Distribution of energy by atmosphere and ocean

• “Internal” variability (Redux)– Analysis

• How weather and climate is organized– Physical geography– Rotation of Earth

• Climate variability and change

Energy doesn’t just come and go

• The atmosphere and ocean are fluids. The horizontal distribution of energy, causes these fluids to move. That is, weather and ocean currents.

From Building the Radiative BalanceRedistribution by atmosphere, ocean, etc.

SURFACE

2) Then it is redistributed by the atmosphere, ocean, land, ice, life.

Top of Atmosphere / Edge of Space

ATMOSPHERECLOUD

RS

1) The absorbed solar energy is converted to terrestrial thermal

energy.

Consider the Distribution of EnergyLatitudinal dependence of heating and cooling

SURFACE

ATMOSPHERECLOUD

Equator(On average heating)

North Pole(Cooling)

South Pole(Cooling)

Because of tilt of Earth, Solar Radiation is absorbed preferentially at the Equator (low latitudes).

Top of Atmosphere / Edge of Space

After the redistribution of energy, the emission of infrared radiation from the Earth is ~ equal from all latitudes.

Transfer of heat north and south is an important element of the climate at the Earth’s surface.

Redistribution by atmosphere, ocean, etc.

SURFACE

Top of Atmosphere / Edge of Space

ATMOSPHERECLOUD

heat is moved to poles

cool is moved towards equator cool is moved towards equator

This is a transfer. Both ocean and atmosphere are important

This predisposition for parts of the globe to be warm and parts of the globe to be cold means that measuring global warming is difficult. Some parts of the world could, in fact, get cooler because this warm and cool pattern could be changed. What is a scenario for record cold temperatures in northern Mexico?

Transport of heat poleward by atmosphere and oceans

• This is an important part of the climate system.

• One could stand back far enough in space, average over time, and perhaps average this away.

• This is, however, weather ... and weather is how we feel the climate day to day– It will change because we are changing the

distribution of heating and increasing the energy in the system.

Internal Variability

Sources of internal variability

• There is “natural” variability. – Solar variability– Volcanic activity– Internal “dynamics”

• Atmosphere - Weather

• Ocean

• Atmosphere-ocean interactions

• Atmosphere-ocean-land-ice interactions

• “Natural” does not mean that these modes of variability remain constant as the climate changes. Separation of “natural” and “human-caused.”

Some Aspects of Climate Variability

• One of the ways to think about climate variability is to think about persistent patterns of weather– Rainy periods

• Floods

– Dry periods• Droughts

• During these times the weather for a region does not appear random – it perhaps appears relentless

An example of variability: Seasons

Tem

pera

ture

Winter WinterSummer

Cold ColdWarm

Rain comes in

fronts

Rain comes in thunderstorms

Mes

sy

Mes

syForced variability

responding to solar heating

Wave Motion and Climate

Year-to-Year Changes in Winter TemperaturesDifferences Relative to 1961-1990 Average

Late 1970s

2006-2011

From Jim Hurrell

Modes of Climate Variability

• Weather – single “events” – waves, vortices• There are modes of internal variability in the

climate system which cause global changes.– El Niño – La Niña

• What is El Niño

– North Atlantic Oscillation• Climate Prediction Center: North Atlantic Oscillation

– Annular Mode– Inter-decadal Tropical Atlantic

– Pacific Decadal Oscillation

What is short-term and long-term?

25 years 50 years 75 years 100 years0 years

ENERGY SECURITY

ECONOMYCLIMATE CHANGE

Pose that time scales for addressing climate change as a society are best defined by human dimensions. Length of infrastructure investment, accumulation of wealth over a lifetime, ...

LONGSHORT

There are short-term issues important to climate change.

Election time

scales

Time Scales of Variability

25 years 50 years 75 years 100 years0 years

El Niño / La Niña

Arctic Oscillation

Pacific Decadal Oscillation

LONGSHORT

Atmosphere-Ocean Interaction: El-Niño

Changes during El Niño

Some good El Niño Information

• NOAA Climate Prediction: Current El Niño / La Niña

• NOAA CPC: Excellent slides on El Niño

GISS Temperature 2002

1997-98 El Niño

January 2011 Temperature Anomalies

El Niño / La Niña Signal

Modes of Climate Variability

• Weather – single “events” – waves, vortices• There are modes of internal variability in the

climate system which cause global changes.– El Niño – La Niña

• What is El Niño

– North Atlantic Oscillation• Climate Prediction Center: North Atlantic Oscillation

– Annular Mode– Inter-decadal Tropical Atlantic

– Pacific Decadal Oscillation

North Atlantic Oscillation

Positive PhaseU.S. East, Mild and Wet

Europe North, Warm and WetCanada North & Greenland, Cold and Dry

Negative PhaseU.S. East, Cold Air Outbreaks, Snow (dry)

Europe North, Cold; South, WetGreenland, Warm

January 2011 Temperature Anomalies

Arctic OscillationSignal

Modes of Climate Variability

• Weather – single “events” – waves, vortices• There are modes of internal variability in the

climate system which cause global changes.– El Niño – La Niña

• What is El Niño

– North Atlantic Oscillation• Climate Prediction Center: North Atlantic Oscillation

– Annular Mode– Inter-decadal Tropical Atlantic

– Pacific Decadal Oscillation

Pacific Decadal Oscillation

• Does the Pacific Decadal Oscillation operate regularly lasting 20-30 years, and does southern California experience droughts during that period?

• The Pacific Decadal Oscillation is one of several “oscillations” that are important to weather and climate.

• Some attributes of the Pacific Decadal Oscillation

Pacific Decadal Oscillation: Basics

Better version of figure from JISAO

Colors: Sea Surface Temperature difference from long term average.Arrows: Stress on the ocean surface caused by winds

Warm here Cool here

January 2011 Temperature Anomalies

Pacific Decadal Oscillation Signal

Some information on Pacific Decadal Oscillation

• Joint Institute for Study of Atmosphere and Ocean (JISAO): – Pacific Decadal Oscillation

• Climate Prediction Center (CPC): – 90 Day Outlook Summary– Weather and Climate Linkage

• National Climatic Data Center (NCDC):– Decadal Oscillations

• Review Paper from Rood Class References– Mantua and Hare (2002) J of Oceanography

How Weather is Organized

Projected Global Temperature Trends: 2100

2071-2100 temperatures relative to 1961-1990.Special Report on Emissions Scenarios Storyline B2 (middle of the road warming).

IPCC 2001

Heat CapacityHeat Transport Land

Projected Global Temperature Trends: 2100

2071-2100 temperatures relative to 1961-1990.Special Report on Emissions Scenarios Storyline B2 (middle of the road warming).

IPCC 2001

Heat CapacityHeat Transport Ocean

Atmosphere

Hurricanes and heat: Sea Surface Temperature

Weather Moves Heat from Tropics to the Poles

HURRICANES

Mid-latitude cyclones & Heat

Projected Global Temperature Trends: 2100

2071-2100 temperatures relative to 1961-1990.Special Report on Emissions Scenarios Storyline B2 (middle of the road warming).

IPCC 2001

Ocean

Ocean Surface Currents(From Steven Dutch, U Wisconsin, Green Bay)

Good Material at National Earth Science Teachers Association

The Thermohaline Circulation (THC) (Global, organized circulation in the ocean)

(The “conveyer belt”, “rivers” within the ocean)

Where there is localized

exchange of water between

the surface and the deep

ocean (convection)

Warm, surface currents.

Cold, bottom currents.

Green shading, high saltBlue shading, low salt

In Class / Groups / Discussion

• Thermohaline Circulation – Atlantic Meridional Overturning Circulation

• In groups discuss Atlantic Meridional Overturning Circulation / Gulf Stream– How does it affect climate?– How does variability affect climate?

• Consider:– Temperature, Ice Melting, Wind, Saltiness,

Climate variability and change

Time Scales of Variability

25 years 50 years 75 years 100 years0 years

El Niño / La Niña

Arctic Oscillation

Pacific Decadal Oscillation

LONGSHORT

January 2011 Temperature Anomalies

El Niño / La Niña Signal

GISS Temperature 2002

1997-98 El Niño

Roles of Uncertainty / Variability at Different TimesHawkins and Sutton, 2009

Summary: Class 9, Winter 2015

• Distribution of energy by atmosphere and ocean– Greenhouse gases change energy balance– Atmosphere and oceans transport energy

• “Internal” variability (Redux)– Modes of internal variability organize weather

in spatial and temporal patterns

Summary: Class 9, Winter 2015

• How weather and climate is organized– Rotation of Earth– Location of land-water– Tilt of axis– Thermal characteristics

• Climate variability and change– Climate change occurs on a background of

variability.– We can diagnose the variability, it is more difficult

to predict.

Outline: Class 9, Winter 2015

• Distribution of energy by atmosphere and ocean

• “Internal” variability (Redux)– Analysis

• How weather and climate is organized– Physical geography– Rotation of Earth

• Climate variability and change

Projects

• Abrupt climate change

• Consequences of rapid change in the Arctic

• Analysis of the warming “hiatus”