weather climate Flashcards
what is climate compared to weather?
climate is the long term weather of a place.
hadley cell
warm air rises at the equator, as it rises it cools and generates large amounts of precipitation. Air cools and generates large amounts of precipitation. Air cools and then moves away from the equator, the dense air then falls towards the earths surface. As it does this it warms and tends to reduce precipitation, once air reaches the equator pressure differences cause it to move back to the equator.
coriolis effect
as the air moves about the surface of the earth this means and the planet continues to rotate. If a mass of air moves north from the equator over a large difference it will appear to have been deflected to the right this is because the earth has rotated below the air.
solar variation
the amount of radiation that the earth recievess from the sun changes over time. Lower solar activity is likely to lead to glacial periods
volcanism
larrge scale volcanic eruptions can eject huge volumes of ash and dust into the atmosphere
. SOme eruptions can block out solar radiations
surface impact
asteriodes can eject large amounts of dust into the atmosphere and therefore this can block out solar radiation and leading to glaial period
What is a jetstream
fast flowing air currents in the atmosphere of the world. Often found at boundaries of circulation cells.
ocean circulation
surface ocean currents are driven by the movement of wind across the top of the water. deep ocean currents are driven by water sinking and rising. both current s are deflected north by the coriolis effect.
How does axal tilt affect the temperature of the earth
Over a period of 40,000 years the angle of the tilt changes. This sometimes means winters are colder and summers are wamer vice versa. When tilted closer to the sun the difference in seasons is less
precession
the earth rotates on its axis, and it doesn’t do that perfectly. The earth eeffectively wobbles on its axis in a similar way to a spinning top. This affects our seasons by creting either greater or smaller differences. Every 24,000 years changes.
eccentricity
when the orbit of the earth changes from being more circular to more eliptical, when mroe eliptical it is colder as the sun is further away from the earth so creates a glacial period.
negative impacts of climate change
food production: With temperatures being too high too grow around the equators in some places this leads to a low crop yield causing a food shortage in some places.
Maldives: the nearly 400,000 people will have to be evacuated if the trends continue.
glaciers: Melting of glaciers in the himalayas can lead to flooding of towns in india and pakistan and cause irrigation of water.
