Climate change

What is climate change

Climate change is the long-term change in global weather patterns

Weather

Day-to-day changes in the conditions of the atmosphere

Climate

Average weather conditions for a location, measured over a period of 30 years

What I need to know about climate change

Climate change is the result of natural and human factors and has a range of effects

Evidence of Climate Change

Tree rings. Ice cores. Glacial retreat. Historical Records. Temperature records

Tree rings

A tree grows a new ring every year. In warmer and wetter years, the rings are thicker. Tree rings can reveal evidence of temperature and weather changes over the past 10,000 years

Ice cores

Scientists drill into ice to removes their core. Each layer in an ice core is a frozen record of the snow that fell that year. By studying gases trapped inside the ice, scientists can tell the Earth was warmer or colder. Lots of carbon dioxide means the Earth was warmer

Human causes of Climate Change

Use of fossil fuels. Agriculture. Deforestation

Use of fossil fuels

When burning fuels like coal, oil and natural gas they release large amounts of carbon dioxide into the atmosphere - which are contributors of the enhanced greenhouse effects helping climate change.

Deforestation

Trees absorb carbon dioxide through photosynthesis, acting as a carbon sink. When trees are cut down the stored carbon is released back into the atmosphere as carbon dioxide, increase greenhouse levels contributing to climate change.

Argiculture

Livestock and rice farming produces huge amounts of the greenhouse gas methane. It is released by animals during digestion and by matter decomposed by microbes in flooded rice paddy fields

Natural factors of climate change

Volcanic eruptions. Orbital changes. Solar output. Asteroids

Volcanic eruptions

Volcanic eruptions release ash and gas into the atmosphere, if they are high enough they can travel around the Earth - which forms a blanket around Earth and reflect sunlight radiation back into space making the Earth cooler.

Asteroids

As they impact it throws up million of tonnes of ash and dust into the atmosphere, blocking out the Sun, making the Earth cooler

Solar output

The solar energy from the Sun varies over time, which results in changes to the Earth’s climate. The last 50 years, the Sun’s energy output has declined slightly despite the rise in global temperatures.

Orbital changes

The Earth’s orbit changes from a circular orbit to an elliptical orbit affecting its distance from the Sun. When the orbit is circular, the Earth is closer to the Sun and the temperature will increase. When the orbit is elliptical , the Earth is further from the Sun and the temperature will decrease

Effects of climate change on the environment

Environment: Warmer temperatures causing glaciers and ice sheets to melt, leading to rising sea levels causing flooding. Biodiversity loss due to the habitats being damaged by climate change.

Effects of climate change on the people

Food and water shortages due to droughts and reduced crop yields. Many coastal areas at risk of flooding and inhabitable areas leading to overcrowding .

Managing Climate Change: Mitigation

Reduces the causes of climate change: Carbon capture, Planting trees, International agreements, Alternative energy production

Carbon capture

Capturing carbon dioxide released by industry or through burning fossil fuels and then storing it safely underground. The Norcem Cemant Plant in Norway captures carbon dioxide emissions using this strategy

Planting trees

Afforestation reverse the effects of deforestation as carbon dioxide is removed from the atmosphere. The Denmark government is planning to replace farmland with a new forest to help mitigate climate change

Alternative energy production

Using renewable energy sources to reduce less greenhouse gases than burning fossil fuels. The EU’s Renewable Energy Directive sets a binding target of 20% final energy consumption from renewable sources

International agreements

Countries agree to reducing greenhouses gases by a set amount by a certain date. Paris Agreement is one of the main agreements signed by over 170 countries

Managing Climate Change: Adaptation

To cope with the impacts of climate change: Changes in agricultural systems, managing water supply, reducing risk from rising sea levels

Reducing risk from rising sea levels

Physical defences such as sea walls and barriers, reducing the risk of flooding. Elevated buildings- buildings being raised on stilts or elevated foundations.

Managing water supply

Water supply can be increased by desalination and recycling rainwater and water meters are installed to encourage reduce water use

Changes in agricultural systems

Farmers are adopting drought resistant crop varieties to cope with changing weather patterns and using improved irrigation systems to manage water sufficiently during dry periods