Changing Climate Flashcards
Galacial
A cold phase
-The little ice age
Intergalacial
A warm phase
-The Medieval Warm Period
Types of evidence of climate change
Ice and sediment cores
Tree rings
Pollen analysis
Temperature records
Ice and sediment cores
A layer of ice is formed each year to form an ice sheet
Scientists drill into the ice and grey long cores of ice
The gasses inside the sheets show what the temperature was each year
They show the past 400,000 years
Tree rings
Trees grow a new ring each year, they’re thicker in warm and wet conditions
They can show how the climate has changed for the past 10,000 years
Pollen analysis
Pollen from plants gets preserved in sediment
Scientists identify and date the pollen to show which species were living at the time
They know the conditions that plants live in now so pollen from similar plants show the clime was similar
Temperature records
Since 1850s global temperatures have been taken using thermometers
Accurate but short term
Causes of climate change
Orbital change
Volcanic output
Solar output
Human activity
Orbital changes
The way the earth moves round the sun
This changes the amount of solar radiation the earth receives
Orbital changes may have caused the galacial and intergalacial cycles
Volcanic activity
Major volcanic eruptions let out gasses and ash into the atmosphere which reflect the suns rays and cools the earths temperature
They release CO2
Solar output
Sums output isn’t constant
It changes in cycles of about 11 years
When solar output is reduced the earths climate becomes cooler
Most scientists think this isn’t a major effect
Human activities contributing to global warming
Cement production
Deforestation
Burning fossil fuels
Farming
The enhanced greenhouse effect
The green house effect that’s being made worse by human activity
Environmental effects of climate change
Ice sheets melt-like Greenland Polar habitats destroyed Sea levels rise, islands like the Maldives will be flooded more regularly Coral reefs suffer from bleaching Precipitation pattern changes
Social effects of climate change
Deaths from heat have increased, and decreased from cold
Low lying coastal areas could be flooded and houses are lost
Farming could be destructed
Could reduce water availability
Lower crop yields-increase malnutrition, ill health and death from starvation
Weather gets more extreme, more money has to be spent on predicting weather events, reducing the impacts and rebuilding after them
