+ YEAR 10EARTH AND SPACE SCIENCE (ESS)

+EARTH & SPACE SCIENCE

2 parts to the unit:

EARTH – Global systems

& SPACE – Origins of the universe

We’re going to do the Space part first

+UNIT REQUIREMENTS

Star quiz

Planetarium Excursion Assignment

Orbits Experiment – How do planets move?

Greenhouse Experiment Report

Carbon Cycle Diagrams

Great Barrier Reef Video

(on Thursday)

(due Thursday)

+EARTH

The Greenhouse Effect

The Carbon Cycle

Global warming – effects of deforestation

Global warming – impact on arctic ecosystems

+THE GREENHOUSE EFFECT

Radiation enters the Earth’s atmosphere

This provides warmth and light

The short wave radiation can be reflected back into the atmosphere.

However, the long-wave radiation gets trapped by the gases in our atmosphere and cannot escape. It returns back to the surface to continue warming.

Greenhouses gases (like CO2) enhance this effect.

+THE GREENHOUSE EFFECT

+THE GREENHOUSE EFFECT

+THE GREENHOUSE GASES

Carbon dioxide (CO2)

Methane (CH4)

Nitrous oxide (N2O)

+THE GREENHOUSE GASES

+THE GREENHOUSE EFFECT

1. Depletion of ozone layer letting in more ultra violet light (UV) .

2. Build up of greenhouse gases keeps more reflected radiation in

+THE CARBON CYCLE

+THE CARBON CYCLE

The carbon cycle includes:PhotosynthesisCell respirationCombustionFossilisation

+THE CARBON CYCLE

Photosynthesis removes CO2 from the atmosphere

Cell respiration, combustion and fossilisation all lead to an increase in levels of CO2

Human impact is increasing the release of CO2 into the environment

+GLOBAL WARMING

Photosynthesis in plants

More trees - more CO2 is taken from the atmosphere

Less trees (deforestation) – less CO2 removed from the atmosphere increased greenhouse gases global warming

+GLOBAL WARMING

Decomposition and fossil fuels

Decay of living things releases CO2

Dead material forms fossil fuels (coal, oil and natural gas) which release CO2 when burned

It is the combustion of fossil fuels in factories, cars, etc that can lead to carbon emissions and possible global warming.

+GLOBAL WARMING

Global temperatures have risen ~1-40C:

More hot days, fewer cold days,

Increased rainfall in NE of Australia, decrease rainfall in the south

More bushfires and destructive tropical cyclones

+GLOBAL WARMING

The trends in atmospheric gases are studied as indicators of potential climate change.

The analysis of CO2 trends is complex. eg. there are seasonal fluctuations in levels of

atmospheric CO2

Data taken from Vostok, Antarctica

+GLOBAL WARMING

+GLOBAL WARMING

Long-term Trends: CO2 levels fluctuate with ice ages and warm ages

Short-term Trends: CO2 levels are higher than any time in last 400,000

years (and are still rising)

+GLOBAL WARMING

Sea levels have risen:

Increased 10-20cm last 100 years

Further rises due to:Warming ocean water and resulting thermal

expansionMelting of glaciers and polar ice caps

+GLOBAL WARMING

Permafrost is thawing:

Carbon locked in the permafrost will be released

Collapse of buildings and coastal cities

Huge impact on Arctic and Antarctic ecosystems

+GLOBAL WARMING IN THE ARCTIC

+GLOBAL WARMING IN THE ARCTICThe average temp in the Arctic region is rising at twice the speed of the rest of the world.

The polar cap is shrinking as a result.

The snow and ice cover the Arctic reflects much of the Earth’s radiation.

When this melts, the Arctic will absorb more heat and warm up even faster!

This may also release CO2 stored in ocean (increasing warming).

+GLOBAL WARMING IN THE ARCTIC Diminished snow cover and permafrost

Increased decomposition of detritus and burning of fuels (once trapped in permafrost)

Expansion of ranges of habitats available to temperate species (loss of tundra)

Increased success of pest species and pathogens (leads to extinction of native species)

Changed behaviours of native species (e.g. migration, hibernation, birth cycles)

Extinction and loss of biodiversity

China and US agree on ambitious greenhouse gas emissions targets

Updated 13 Nov 2014, 12:24amThu 13 Nov 2014, 12:24am

China and the United States have agreed on a set of ambitious greenhouse gas emission targets, with Beijing setting a goal for its emissions to peak "around 2030".

It is the first time China, the world's biggest polluter, has set a date for its emissions to stop increasing, and the White House said China would "try to peak early".

At the same time the US set a goal to cut its own emissions of the gases blamed for climate change by 26-28 per cent from 2005 levels by 2025.

http://www.abc.net.au/news/2014-11-12/china-and-us-agree-on-ambitous-gas-emissions-targets/5886200