Changing Climate

Quick Starter …

In 2008 there was a global summit regarding Global Warming … 193 representatives from the worlds countries agreed to sign an anti CO2 emissions treaty. There are 195 recognised countries … Which 2 countries did not sign?

Answer

The USA and China … The USA was under control by Republican George. W .Bush, he did not believe in Global Warming so neither did his supporters. China on the other hand make far too much money from the Earth’s natural resources to care … They also have a very strong communist government which do not allow talk such as climate change to reach its people.

The Earth’s Climate

The previous graph shows how an increase in CO2 correlates with our temperature … But why does the temperature shoot up after the 1800’s?

Of course … The Industrial Revolution!

But what is it?

Where Are We Now?

When the temperature drops it is called a glacial period or an Ice Age. This is when the Earth is covered in ice.

However, we are in a period of warming … an interglacial period.

Where Did I Get This From?

This data is generated from fossils and ice cores. Ice cores are cylinders of ice, obtained by drilling 3km deep into glaciers which are over 500,000 years old!

Natural Causes of Climate Change

• Volcanic Eruptions pump ash and gas into the atmosphere causing a cooling effect – You wouldn’t think so would you? If you touched a pool of lava it would boil your blood and your finger would be disintegrated instantly.

• Sun Spots: Amount of energy radiated from the Sun changes over an 11 year cycle.

• Ocean Currents changing can cause cooling and warming. In the UK, we get our warm air via the Golf Stream – bringing warm air from the Caribbean.

• Large asteroid collisions can cause cooling as massive blocks of material can block out the sun. Asteroids hitting the Earth can cause huge fires … Releasing massive amounts of CO2.

• The Earth’s orbit changes a small amount once every 10,000 years. These are known as Milankovitch cycles.

Our Climate

• We live in a temperate maritime climate, cold winters and warm summers.

• However, even though being on the same “line” as us they have a Polar Maritime climate. So apart from the Summer it will snow, rain and be below freezing.

Quick Question …

Describe what is meant by the term Ice Age?

Answer

An ice age is a period of long-term reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers.

The Little Ice Age

A colder period in Northern Europe starting in the 1400’s lasting to the mid 19th century.

Crops stopped growing which meant less food for people … Converse?

The winters were very cold and the summers short.

Causes and Evidence

• Fewer Sun Spots and volcanic ash. But not by humans … Why?

• We know this through newspapers, diaries and tree rings – they are thinner in colder weather.

Impact on Mega Fauna

Fauna is AnimalsFlora is Plants

Mammoths and Sabre tooth Cats could not adapt to a warmer climate and died.

Quick Question …

Describe one impact of a colder period?

Answer

When there was a little Ice Age in the 1400’s the growing season was shortened for crops. People eventually went hungry.

Present and Future Climate Change

• CH4 (methane) and CO2 are greenhouse gases linked to human activity.

• Rise in Greenhouse Gas Emissions match start of Industrial Revolution.

• Current Levels of CO2 are thought to be at their highest for 650,000 years.

• Current levels of CH4 are thought to be at their highest for at least 900,000 years.

• Methane is 21 times more potent than CO2

Methane V Carbon Dioxide

The Greenhouse Effect

• As a country develops, the gases it release increases.

• More CO2 is produced due to more industry, transport – petrol is needed, and deforestation.

• Methane is produced due to an increased demand for farm animals.

Quick Question

Describe one human activity that is thought to contribute to climate change?

Answer

• Burning coal for electricity because it releases CO2 which is a greenhouse gas linked to global warming.

The UK Climate• Our climate is classed as “mild” and geographically

described as having a “temperate maritime” climate.• We have this climate because of several reasons …• Latitude affects how much sun the UK gets and how strong

it is in different seasons.• The North Atlantic Drift keeps us warmer than other

countries of the same latitude.• Air masses bring weather conditions with them from where

they originated … The UK has 5 air masses.• Prevailing winds from the Atlantic Ocean in the south west.

They pick up moisture from the sea and bring rain to the UK

Our Climate Changing … • Potential changes … average temperature rise, less

predictable rainfall patterns, changing seasons could include more extreme weather.

• These will happen because … The Gulf stream will move which will reduce sea temperatures and bring less rainfall.

• More northern air masses will come down, bringing more storms and perhaps more extreme cold weather.

• Paths of depression that bring rainfall may alter.

Using CO2 Levels To Predict Effects Of Climate Change

• If CO2 concentrations go over 550ppm, global temperatures could rise by more than 6 degrees Celsius. This could lead to millions of homes being claimed by the sea, changes to the world’s weather patterns could lead to droughts and storms leading to disease and famine … animals and plant species may not be able to adapt to the changes.

However …

• If concentrations stay below 550 ppm, the global temperature will not rise over 2 degrees Celsius. So maybe the sea level will rise by 1 metre causing coastal flooding, hurricanes would be more frequent and some species may become extinct.

Quick Question …

• If the ice caps completely melt, then the Gulf Stream will switch off … What will that mean for the UK climate?

Answer

• Surprisingly, the temperature will not get hotter … but much colder. We will stop getting the warm air from the Caribbean and as we are at the same latitude as Canada we will get the same weather as them … So more days off school!

Environmental Impacts• Sea Level rise will lead to loss of coastal land and

increased erosion.• More severe storms and longer summer droughts.• Changes to fishing industries – out migration.• Ecosystem change could mean some plant and

animal species move into new areas.• Warmer temperatures could encourage diseases

like malaria.

Economic Impacts• An increase in refugees from other countries hit hard by

climate change in UK.• Warmer weather means that farmers can grow different

crops.• Hotter summers could increase holidays in the UK, so

less people will use planes.• Damage to coastal areas in London will be extremely

expensive and disruptive.• Costs of protecting the coastline will be expensive.• Housing design might need to be altered so that less

water is wasted and higher temperatures are dealt with.

Quick Question …

• Describe some possible economic impacts of climate change on the UK?

Answer• Climate change in the UK could cause flooding

in London. This would prevent businesses making money and it would cost a lot to repair the flood damage. Climate change could also mean less rainfall, causing drought. It would cost money to move water around the country to supply those who need it. However, if the climate was warmer, it might encourage tourism which would make money for the UK.

Climate Change in Bangladesh• Environmental Impacts … River Flooding

would become even worse from heavier rains and sea level rise.

• Tropical storms could become more frequent and may move further inland, doing more damage.

• The dry season is already getting longer and this could cause more droughts.

Economic Impacts• A small rise in sea level could massively reduce farmland and agricultural

output.• More river flooding would lead to damage to houses meaning disruption

in economic terms and peoples lives.• More intense tropical storms spreading inland would mean more

damage to infrastructure.• Farmers need land to work but Bangladesh has a fast growing

population.• The cost of protecting homes and businesses from flooding is very

expensive.• Coastal flooding could make the farmland too salty to grow crops on.• Shrimp farming is very important but rising sea temperatures may

damage this form of aquaculture.• Increased flooding will increase the spread of water borne diseases.

Just in Case …

You may want to know the effects climate change has on the Maldives.• Coral Reefs die.• Ecosystem associated with reefs will be lost.• People will be forced to leave home – That’s

400,000 people.• Traditional ways lost.• Tourist industry down … bankruptcy possible.