Welcome! Please get out homework for a stamp: Two questions on RCP’s, bracket map, 10 terms Please...

Welcome!

Please get out homework for a stamp: Two questions on RCP’s, bracket map, 10 terms

Please read the board.

Kahoot practice!

What do these have in common?

Climate and civilization

Human civilizations change when climate changes

20,000 ybp (years before present) ice age: Bering strait freezes, people migrate to the Americas

8,000-7,000 ybp – warming period Mesopotamia flourishing, Jericho established

Mayan civilization – collapses suddenly 950 CE (common era – used to be called AD)Leif Erikson – 950 CE sails to Greenland

Black Death in Europe – famine 1315-1317 – needed to import grain from China

Little Ice age – 1550-1850Irish Potato Famine

Dust Bowl – 1930’s

Mild but persistent La Nina conditions coupled with changes of sea surface temperatures + poor farming practices

SPM 1: Current observations

What details need to be added?

Correlation/causation pg 5

CO2 levels currently

Mauna Loa Observatory - Hawaii CO2 at beginning of Industrial revolution: 280 ppm Current CO2 levels: 398ppm

(watch the movie – when is CO2 highest? Where??? Why???)

Figure 4 – Current observable effects Circle most certain effects What are the implications? Examples from the news? Which is of greatest concern to

Houston/US/you?

SPM figure 5

What are the predictions? How do they get from CO2 to change in

temperature?

Predicting future climate

How do they do that anyway?

Global Circulation model

Global Climate Models: GCM’s

Computer model divides atmosphere into chunks.

Current conditions programmed into each chunk: temp, wind, [GHGs], etc

Computer can generate current and future global temperature averages based on [GHGs]

Limitations of GCMs

Complexity Feedback loops (not included in GCMs)

(+)Melting tundra permafrost and lower geologic formations– 500 billion tons CH4

(+)Loss of albedo effect with ice (-)Increasing albedo effect with clouds (+) Increasing greenhouse effect with evaporating water

Role of ocean and CO2 absorption

Lesson from the Ozone Hole:

1930’s – CFCs invented 1970’s – mechanism of O3 destruction

understood; models of possible effects suggest general thinning of O3 layer

1985 – Ozone hole documented as complete surprise – models were wrong.

1987 – Montreal Protocol ratified

Predictions:

If CO2 goes to 450ppm by 2050, +2oC (3.6oF) CO2 to 550ppm by 2050, +3oC (5.4oF) In 50 yrs, expect 4oC warming (2012 World Bank Report)

CO2 of 350ppm is considered sustainable by climatologists

Tipping point is probably at 2oC (the point at which change due to human activity

brings about sufficient new processes in nature to make any human reversal of the change impossible. )

Homework tonight

Read SPM 2.1 and 2.2 add details to your bracket map.

Studystack.com to review terms: search IPCC terms WHS or carolynklein

Chasing Ice –ice core graphs, effects, glaciers

Big seven effects Change in precipitation patterns More severe weather events (droughts, floods,

extreme hot/cold) Rising sea levels (glaciers melting) Changing seasons – earlier spring and shift of

biomes away from equator Increased insect-borne disease Decreased availability of fresh water Acidification of ocean and bleaching of coral reefs

(H2CO3)

Sea level rise .7 m by 2100

Melting glaciers add water volume to ocean (Greenland ice sheet stores enough water to raise sea level by 5-7 meters)

Thermal expansion creates most of the increase

Where will the environmental refuges go? 50% of global population lives within 100 miles of a coastline.

Fig. 11–9

Shift of biomes away from equatorShift of biomes away from equator

Trees can shift 5mi/10years through seed dispersal

Shift of habitat to higher latitudes and elevations

Potential large loss of biodiversity

© Brooks/Cole Publishing Company / ITP

Don’t forget!