Climate changes from the past
The little ice age happened in England which started on 1608 and ended in 1814.
The impacts of little ice ages is that wheats and oats cannot ripen and also another impact is that 10-20% of farmers would die from hunger.
The uk climate
The UK has a mild mild climate - cool, wet winters and warm, wet summers
Temperature - follows a seasonal pattern. Highest is in July to august avg - 19 degrees
Lowest - january to February average 6 degrees.
The temperature range is 13 degrees.
Precipitation - follows a seasonal pattern. Highest - October to January 120 mm per month
lowest - April to July 70 mm per month.
Fluctuates - february to march
Sunshine hours - follows a seasonal pattern
Highest - may to august 170-80 hours per month
Lowest - December to january 40 hours per monthp
Depression and anticyclone
Deppresions form when warm air meets cold air.
Depression form I've the Atlantic ocean than moves east over the UK.
They form when: warm, moist air meets cold, dry air from the poles
The warm air is less dense so it rises above the cold air
Condensation occurs as the warm air rises, causing rain clouds to develop.
Rising air also causes low pressure at the earths surface
Winds blow into the depression in a spiral. Wind blows from high to low pressure.
A warm front is the front edge of a moving warm air
A cold front is the front edge of a moving warm air.
The causes of climate change in the past
The eruption theory.
Large volcanic eruptions, this produces large amounts of ash and sulfur dioxide.
If the ash and sulphur dioxide rise high enough it will spread around the earth in the stratosphere by high wind levels. The sunlight from the sun is blocked and this then cools the planet and lowers the average temperature.
An example is the volcano that erupted in the Philippines called mount pinatubo, releasing 17 million tonnes of sulphur dioxide.
The causes of climate change in the past (3)
The orbital theory.
Scientists believe that the changes int he way th earth orbits affects the climate.
The earths orbit is sometimes circular, and sometimes more of an ellipse.
The earths axis tilts. Sometimes it is more upright, and sometimes more on it's side.
The earths axis wobbles, like a spinning top about to fall over.
These three changes alter the amount of sunlight that reaches earth.
These changes are called milankobitch cycles.
Climate of the past
The little ice age.
The little ice age made life impossible for the Greenland Vikings. They ran out of food and died out.
As the world cooled the little ice age began to have wider impacts.
Impacts of little ice age: Made the farming conditions impossible because it needs warmer conditions, the people resorted to the wet loving potatoes. The little ice age caused a lot of problems for the people but they adapted.
Climate and ecosystems
Ecosystems - plants and animals live together in ecosystems, they depend on each other and are linked together in food chains. Also depend on the environment around them. Ecosystems can be small, such as a pond or large, such as tropical rainforest. If one part of the ecosystem changes than so does the rest.
The dinosaurs - 65 millions years ago the dinosaurs became extinct. Two possible causes are: a strike by a massive asteroid in Mexico, a huge volcanic eruption in Deccan in India lasting up to 1 million years. Both of these events events are known to have happened at that time, may have happened together. Both would have thrown up huge amounts of dust, ash and gas into the air, blocking out the sun. Plants would have struggled to live as the climate cooled. Ecosystems would have broken down as food chains collapsed.
Ice age megafauna extinction - This happened after the dinosaurs, about 10,000 - 15,000 years ago. Megafauna means 'big animal' most weighed up to 40kg: woolly mammoth, giant elk, ground sloth, sabre tooth cat,, giant beaver and glyptodon.
UK climate futures
Global warming will make the UK warmer, but precipitation will also change.
In summer if the Uk was hotter by: 2°C - it would be as warm as paris, 4°C - it would be like the south of France, 6°C - It wuld be like Madrid.
A warmer UK will have costs as well as benefits.
Cost of UK: More illnesses, hot temps could melt roads, farmers will have to change crops, plants and animals might die.
Benefits:In winter cost of heating and road gritting might fall, more people would go to the UK for tourism, New crops might mean more sales, More land coud be farmed at higher temperatures.
Wild weather might become more common in the UK. This means more heatwaves, flooding and storms.
We could reduce greenhouse effect by: Use of fossil fuels and switch to 'green energy', use cars less and public transport more.