What is albedo? What might be the consequences of melting sea ice? Learning objective: Discuss the causes and environmental consequences of global climate change – anthropogenic causes What is albedo? What might be the consequences of melting sea ice?

Global climate change The changes in the global patterns of rainfall and temperature, sea level, habitats and the incidence of drought, floods and storms, resulting from changes in the Earth’s atmosphere, believed to be mainly caused by the enhanced greenhouse effect.

Volcanic activity

Changes in long wave radiation returned to space

Recap of the GHGs What are the contributors and impacts of: Carbon dioxide Methane Nitrous oxides Chloroflorocarbons Ozone Describe the sources of three of these using p150-151

Greenhouse gases p150-151 Paul Guinness Source Increase Water vapour Carbon dioxide Methane Chloroflorocarbons Ozone

Highest rate of temperature change in late 20th – 21st century 1990s warmest decade on record Most increases in the mid and high latitudes of northern hemisphere Argument that human activity has significantly increased the amount of greenhouse gases in the atmosphere

Water vapour, albedo, methane Positive feedback

Permafrost – methane store

Alternative views some sceptics believe those who blame the warming of the planet on human activity are alarmists They believe environmentalists use catastrophic climate change to place nature over the needs of people and force the switch from fossil fuels to alternative energy sources, and tends toward "big-government intervention." most climate-change skeptics do concede the planet is warming Instead, they debate the cause, its potential impact, and whether human intervention can affect it. Most debate centres around: Are people responsible for the warming trend? What impact will more warming will have on the planet? Can anything be done about it?

Some of the scepticism comes from suggestions that there may be flaws in the IPCC data such as projecting Himalayan glaciers could melt by 2035 They have also questioned the accuracy of some of the climate models.

Consequences Thermal expansion - 3mm per year Increased acidity – more CO2 absorbed creating carbonic acid – impacts on coral Ice caps and glaciers melting Peat bog thawing Food Water Ecosystems Extreme weather Use p 152 – 154 and annotate onto to your world map

On a post it write down one question that you have about atmospheric change