climate- what you expect the weather to be like somewhere due to averages of a 30 year time
PHYSICAL EVIDENCE WHICH SHOWS CLIMATE IS DIFFERENT NOW, THAN IT WAS FROM THE PAST.
-fossils are found of animals which no longer live in the uk, in the uk
- u shaped valleys left by retreating glaciers
-ice sheets, which contain layers of ice contains air bubbles whcih contain co2. Climatologists can tell past temperatures by measuring amount of co2 trapped in the air bubbles
what happened during the quaternary?
warm periods (interglacials) lasted between 10000 and 15000 years.
cold periods (glacials) lasted between 80,000 to 100000 years
the world became an ice age. There were so many ice sheets and they were so heavy they made the earths crust sag. So much water locked into these ice sheets the sea level dropped by 100m
WHAT IS EVIDENCE FROM RECENT TIMES THAT THERE HAS BEEN CLIMATE CHANGE?
-old photos and drawings and paintings of landscapes
-written records e.g books and newspaperd and diaries
-record dates of migrating birds, harvest and trees blossom
HOWEVER these sources arent very accurate as they are not intending to record climate, but do give us some idea of climate trends in the past
what is the eruption theory?
-big volcanic eruptions can change the earths climate by production ash and sulfur dioxide
-when the ash and gas move high enough, they spread around earth in the stratosphere by high levels of wind. This stops the earth recieving sunlight and instead reflects it off into space cooling the planet down.
HOW CAN AN ASTEROID COLLISION IMPACT CLIMATE
-blast million tonnes of ash and gas into the stratosphere which block sunlight
sun spots and solar output
-black spots on the earths surface, which tell us the sun is more active. Lots of spots mean more solar energy is being fired off onto earth
-the earths orbit can be circular or oval
-the axis tilt
--these can alter where sunlight hits the earth and affect the amount of sunlight
what happened to the vikings on greenland
-deforestation and soil erosion made it very hard to produce food
-sea ice stopped trade with iceland and norway
-animals did not survive the cold weather
-people were fighting over many resources
-people died out
how did the little ice age affect the uk
-river thames froze over
-famine begun and many poor people died of starvation as harvest failed
-glaciers grew down valleys which destroyed villages and farmland
WHAT HAPPENED DURING THE MEDEVIL WARM PERIOD?
-population grew -newland given to farming -
what happened to the dinosaurs
became extinct due-
-massive asteriod - large volcanic eruption in india lasting 1 million years
Both would of thrown up huge amounts of gas and ash which would reduce amount of sunlight and stopped plants from growing.
-megaufuana area group of aniamls who become extinct, each weighing 40 kg consisting of a sloth, mammoth and beaver.
DUE TO CLIMATE CHANGE AND HUMANS THEY DECIDED TO MOVE AWAY
-finding right plants to eat in areas was difficult
-disrupted foot chains
-made them weaker
-humans also began to hunt them which would affect food chains
green house effect
green house effect is natural and its what keeps us warm, without it earth as we know it would be frozen
HOWEVER- we are adding extra lot of the gases into it, which increase climate change
GLOBAL WARMING HAS BEEN CAUSED BY THIS
-which rises sea levels due to thermal expansion due to glaciers melting
air masses and seasons
-air masses have very strong influence on precipitation, temperature, air pressure, wind and cloud cover. in winter the polar and artic air mass moves south over the uk, in the summer this moves north allowing tropical air masses to move up
maritime climate- close to the sea,moist air moving from the sea cools the summer months but warms the winter months, bringing rain all year round
continental climate- occur far from the sea in the middle of continents,the climate is drier, with hotter summers and colder winters
what are the cost and benefits of warmer weather i
-heating and road gritting costs will be shorter
-more peopleholiday in the uk making economy boom due to tourists
-fewer deaths of people due to cold winter weather
-new crops could be grown
-land could be farmed at higher altitudes
-illness from sun stroke and cancer
-hot temps can melt roads and buckle rail way lines
-farmers might have to change crops to those that need less water and more sunshine
-some plants an animals may die out
-sunscreen will be more expensive -more storms
affect on egypt
-desertification (SAHARA DESERT) caused by over grazing
-falling crop yield due to less water
-more illness such as cancer, heat stroke and malaria
-river nile is its only water supply and could dry up
-sea level rising will get rid of its city alexandria
--less farming will lead to famine
-dams built in uganda are having a srious impact on water reaching egypt