Climate change (7.2)

Nagative feedback mechanisms in climate change

- increased evaporation in low latitudes due to high lvls of precipitation - increase in CO2 in the atmosphere leads to increased plant growth

Examples of positive feedback mechanism in climate change

- melting of polar ice lowers ALBEDO - increased CO2 released from increased biomass decomposition - tropical deforestation increases warming and drying -increases forest cover decreases albedo

WHY do some ppl don't belive in the human caused climate change?

1. Greenhouse gases can be produce by natural: volcanic activity; release of methane by animals and peat bogs; sunspot activity 2. Earth's tilt and variation in orbit around the sun leads to seasonal and regional changes in temperatures 3. Ocean currents can lead to warming or cooling 4. Global dimming: the cooling effects of air pollution

TECHNOCENTRIC approach

A technocentric viewpoint argues that technological developments can provide solutions to environmental problems. This is a consequence of a largely optimistic view of the role humans can play in improving the lot of humanity.

ANTHROPOCENTRIC approach

An anthropocentric viewpoint argues that humans must sustainably manage the global system. This might be through the use of taxes, environmental regulation and legislation. Debate would be encouraged to reach a consensual, pragmatic approach to solving environmental problems.

ECOCENTRIC approach

An ecocentric viewpoint integrates social, spiritual and environmental dimensions into a holistic ideal. It puts ecology and nature as central to humanity and emphasizes a less materialistic approach to life with greater self-sufficiency of societies. An ecocentric viewpoint prioritizes bio-rights, emphasizes the importance of education and encourages self-restraint in human behaviour.

viewpoints on climate change

Ecocentric Anthropocentric Technocentric

Uncertainty of the climate models

How much is the planet warming Where will the impacts of global warming be felt most acutely

Complexity of the problem

I. On a huge scale: atmosphere, the oceans and the land II. Not all feedback mechanisms are fully understood III. Many impact and processes are long-term

examples of human contribution:

The burning of fossil fuel which releases CO2 Deforestation affects earth's ability to absorb CO2 Agriculture increase the CH4 lvl Use of fertilizers lead to higher NOx

Human activities are increasing levels of greenhouse gases (GHGs, such as CO2, CH4 & H2O vapor) in the atmosphere, which leads to

a rise in SEA LVL an increase in the global TEMP. increased frequency and intensity of EXTREME WEATHER events the potential for LONG-TERM CHANGES in climate and weather patterns

the potential impacts of climate change may vary from one location to another and may be perceived as either Adverse or BENEFICIAL. These impacts may include

changes in WATER AVAILability, distribution of biomes and CROP growing AREAS, LOSS of BIODIVER and ecosystem services (extinction of species in wild as many could not adapt to sudden climate change) coastal INUNDATION ocean ACIDIFICATION damage to human HEALTH (spread of tropical diseases)

weather

describe the condition in the atmosphere over a short period of time

climate

describes how the atmosphere behaves over relatively long periods of time

Discuss the feedback mechanisms that would be associated with the change in mean global temperture

examples of negative and positive feedback on the ocean: on the polar ice: pollution: atmosphere: