Climate Change

Define climate change

A district change in global or regional patterns of climate such as changes in temperature or precipitation patterns

What is the Quaternary Period 

Is the most recent geological time period finding from about 2.6 million years ago to the present day 

During the coronary period there have been many fluctuations between a cold glacier period and warmer glacier periods 

Name all the evidence for climate change

Ice and sediment

Tree rings

Pollen analysis

Temperature record

ice and sediment cores

Ice sheets are made up of layers of ice one layer is formed each year

Scientist drill into ice sheets to get long cause of ice

By analysing the gases trapped into the layers of ice, they can tell what the temperature was each year

One ice cream from Antarctica shows the temperature changes over the last 400,000 years

The remains of organisms found in cause taken from ocean sediments can also be analysed. This can extend the temperature record back at least 5 million years

Tree rings

As a tree grows it forms a new ring each year the tree rings are thicker in warm wet conditions

Scientist take and count the rings to find the age of a tree the thickness of each ring shows what the climate was like

Tree rings are a reliable source of evidence of climate change for the past 10,000 years

Pollen analysis

Pollen from plants get preserved in sediment, e.g at the bottom of lakes or in peat bogs 

Scientists can identify and preserve pollen to show which species while living at that time

scientist know the conditions that plants live in now so preserved pollen from similar plants showed that climate conditions were similar

Temperature records

Since the 1850s global temperatures have been measured accurately using thermometers this gives a reliable but short term record of temperature change historical records like harvest dates on newspaper weather report can extend the record of climate change further back

What are the three natural factors that are possible causes of climate change

1. Orbital changes

2. Volcanic activity

3. Solar output

How does orbital change cause climate change?

Orbital changes affect how much solar radiation (energy) the Earth receives more energy means more warming.

These are variations in the way that earth orbits the sun 

Stretch the earth orbits around the sun varies from circular to this is also called eccentricity