Weather and Climate

Name 3 facts about the gulf stream.

- 10,000 km in length - travels at 2 meters/second - brings 100,000,000 m^3 per second to europe - we would need 1,000,000 nuclear power plants to produce the same heat that the gulf stream brings to Europe.

What are the three Milankovitch cycles ?

- Eccentricity - Axil Tilt - Precession

What impact might climate change have on the gulf stream ?

- Polar caps melt salt content in the water would fall and so would its density. - North Atlantic current would not be heavier enough and so it would sink instead. - This would reduce movement in the gulf stream and could bring into a stop.

Explain how the gulf stream works.

- SE trade wind drives warm surface water into the gulf of Mexico where it heats up to 30 degree. - Coriolis effect directs gulf stream towards Europe and splits it up releasing a lot of heat into the atmosphere as the North Atlantic current. - Water becomes colder in northern latitudes. Salt content and density increases on account of evaporation and it drops down between Greenland, Norway and Iceland. - This creates a strong maelstrom which constantly pulls new water and is the reason the gulf stream moves towards Europe.

Since 1960 what has the global average temperature and carbon dioxide concentration increased by?

1 degree 75ppmv

How much rainfall do arid environments get a year?

10-250 mm per year.

Describe the features of the eye of a storm.

20-60 km across. Calm, warmer air. Clean skies and little cloud cover. Air is descending. Kept clear by centrifugal force.

Give 3 facts about the negative impact of climate change on food production.

2050, 10 million more kids malnourished in Africa. 2100, 40% less rainfall in Africa.

What conditions must be present for hurricanes to develop?

26 degree ocean temperatures. Air must be warm and humid. No wind shear; upper level winds should be weak and blowing in direction of developing storm so allow heat to concentrate in vertical area. Low pressure - at least 5 degrees north or south of equator as Coriolis effect will not occur at equator.

Describe global atmospheric circulation through the Polar cells.

60 degrees north and south, warmer FERREL air meets colder POLAR air. Warmer air rises to former POLAR cells. This air travels to poles where it cools and sinks forming areas of high pressure.

What is the thermohalaine convener belt?

A global ocean current that distributes water and heat throughout the oceans.

What is the Quaternary Period?

A subdivision of geological time which covers last 2.6 million years to present day.

What climate does the UK have ?

A temperate climate.

How may the Hadley cell cause aridity?

Air around cancer and Capricorn are dry. Zone of high pressure where the air sinks. This air is dry and no condensation can form or rain.

How may rain shadows cause aridity?

Air is forced to rise over mountains. Air cools and condensation occurs. Rain falls over the mountain. Dry air sinks down the other side of the mountain.

How may continentality affect aridity?

Air is much drier further away from the sea.

What is drought?

An acute water shortage associated with long periods of serious or severe rainfall deficiency.

What is meteorological drought?

An area receives less than average precipitation.

What is the difference between arid environments and drought conditions?

Arid conditions are permanent low precipitation which are located between the tropics and the equator. Drought conditions are temporary low precipitation conditions. Both have high pressure conditions with no cloud cover.

How does intense rainfall from storm surges affect the landscape?

As cyclones move pick up large amounts of water and rainfall. Weather forecasts can estimate rain by seeing how fast storm travels. Leading to flooding. Damage to property. Injury. Flowing water can knock people of their feet.

Describe global atmospheric circulation through the Hadley cells.

At equator, warmed air rises 15km, causing LOW PRESSURE. Air current divides , cools, moves north and south to form HADLEY CELLS. Cooled air sinks at 30 degrees north and south leading to high pressure. Some cool air from HADLEY then moves to equator as trade winds.

How does the UK's Maritime influence in reference to its location influence its climate?

Atlantic Ocean brings moisture. Lack of extreme weather. Sea warms land/temperatures in winter. Sea keeps land/temperatures cool in summer. Moisture resulting in rainfall.

What is climate ?

Average, normal or long term conditions in the atmosphere.

Why is there a higher salt content at the equator?

Bc at the equator more water evaporates which leaves behind more salt creating a higher salt content.

Why do arid and semi arid desserts tend to be between Hadley and ferrel cell?

Because in between two wind circulations more likely to receive less rainfall.

How do tree rings give evidence for climate change ?

Colder periods ring rings closer as growing rates lower.

What are the negative impacts of climate change on food production?

Global warming changes weather patterns. Warmer Climate = much less rainfall. Lack of rainfall leads to desertification and famine. Leads to lower crop yields. Bigger impact on poorer countries.

Describe how deforestation can lead to drought?

Globally increases CO2 levels increasing the GHE causing global warming and climate change resulting in changes in atmospheric circulation and ocean currents. Regionally in large rainforests the transpiration stream means water vapour condenses and falls as daily rain, rising air creates low pressure which pulls in moist from surround areas. This not happen if deforest. W/o trees to intercept rainfall, water cycle disturbed, drop in pressure reduces and therefore less rainfall.

What other evidence do we have for climate change?

Grape harvest records. Journals, diaries etc.

Why has CO2 concentration and temperature risen?

Industry has gone up as global affluence increases. Farming has increased as global population increases. Energy demand increased due to rise in affluence and population. Transport has increased due to higher car ownership. ALL OF THESE EMIT GHG's CONTRIBUTING TO TH GREENHOUSE EFFECT.

How does the UK's altitude in reference to its location influence its climate?

Influences temperature and relief rainfall patterns. Higher and so cooler in highland areas.

What are hurricanes?

Intense low pressure systems that form a cylinder of rising, spiralling air surrounding the eye of descending, high pressure air.

Describe how landslides caused by storm surges affect the environment.

Intense rainfall saturates soil which becomes heavy in areas of steep slopes and will not hold its position. Affects areas of high relief and costal lowlands. Deforestation can make slope unstable. Geology can mean soil can slide easily. Massive devastation to settlements near. Blocks channels causing flooding.

Name some causes one deficiency in rainfall.

Natural variation of cloud cover in the atmosphere. El Niño events. Changing land use. Climate change creating regional and local effects.

What is Axil Tilt ?

Every 40,000 years tilt of Earth's axis varies. Greater Axil Tilt - hotter summer and cooler winter (bigger the difference between summer and winter)

How do ice cores give evidence for climate change ?

Deeper scientists go the further back in time they can go. Analysis of air bubbles indicates climate at the time. If oxygen-18 isotopes instead of oxygen-16 warmer climate.

What are desserts?

Dry or arid areas that receive less than 250mm of rainfall each year. Can be hot or cold. Contain plants and animals especially adapted to dry conditions.

What is procession?

Earth 'wobbles' every 24,000 years on its axis changing the direction the axis is facing affecting differences between seasons.

What is Eccentricity?

Earth's orbit cycle changes every 100,000 years. More circular - cooler periods More elliptical - warmer periods

How will sea level rise affect low lying islands in the Pacific and Indian Ocean?

Eg the Maldives: - tourism 28% countries GDP - could be completely submerged by 2085 - 380,000 people would lose their homes

How does the North Atlantic drift in reference to the UK's location influence its climate?

Gulf Stream brings warm ocean currents that surround the UK. In winter makes UK milder than would be for expected latitude.

Describe how the greenhouse effect works.

Heat energy passes through atmosphere and heats earth up. Much of the heat energy is radiated back into space. Greenhouse gases trap some the radiation causing the temperature to rise and making the earth warmer.

What are the impacts of tropical storms?

High winds Intense rainfall Storm surges Coastal flooding Landslides

What is hydrological drought?

Hydrological (water) cycle receives less rainfall than normal. Less precipitation means less groundwater supplies and reservoirs are not refilled leading to drought conditions.

Give me 2 facts about sea level rise.

IPPC - 2100 20-60cm sea level rise Greenland & Antarctica contribute 6-8 m by 2100.

Describe how ocean currents are formed.

In areas of deficit the water is very cool and dense so it sinks. Warmer water from areas of surplus replaces this surface water creating ocean currents.

Where does drought occur?

In areas where there is far less water compared to what is normal for that area in the same period of time for that year.

How does sun spot activity increase natural climate change ?

Increases solar output.

What are the negative impacts of climate change on sea levels ?

Largely driven by thermal expansion and mountain glacier retreat. Causing floods in short term and sea level rise in long term. Long term contribute to sea level rise.

Give some characteristics of hurricanes.

Largely restricted to ocean areas 30 degrees north and south. Travel west before turning away from the equator. Often 400km wide and 10km high.

Describe some recent temperature changes in the earths climate.

Last 250 years Earth's temp risen significantly. Average temp in last ice age 5 degrees below today's average temp.

How are storm surges formed and what affect do they have on the landscape?

Low pressure and high winds lead to rises in sea level and large masses of water can be dumped onto land. Erode beaches and coastal habitats. Damage costal defences. Flow inland contaminating farmland and fresh water.

Describe the features of the eye wall.

Lowering cumulo-nimbus clouds up to 15km high. Intense instability causes rapid rising of air and encourages cloud development. Heaviest rainfall and destruction.

How does volcanic activity increase natural climate change ?

Major eruptions eject material into the atmosphere where distributed around the globe. Reducing amount of sunlight reaching the earth so temp cools.

How do hurricanes form?

Ocean water reaches 26 degrees. Trade winds converge together near ocean surface. Air rises up to 18 ft. Humid air is pulled into storm; extra water vapour supplies more latent heat. Pre-existing winds join the storm. Storm rotates, accelerating in and up forming a tropical cyclone.

How do high winds from tropical storms affect the landscape?

Over 119km per hour. Cause damage to buildings uproot trees. Sheds and beach huts can be moved. Causing injury and death.

How does Pollen analysis give evidence for climate change?

Pollen extracted in peat bogs and lake bogs. Matching pollen to plants gives an indication of the climate.

How does the UK's latitude in reference to its location influence its climate?

Puts us between Ferrel and Polar cells bringing unsettled conditions.

What does Global atmospheric circulation do ?

Redistributes heat from the equator and the poles.

Describe global atmospheric circulation through the Ferrel cells.

Rest of HADLEY AIR travels towards poles forming the lower part of the FERREL cells.

Describe how dams can cause drought?

Restricting flow of water can lead to a drop in water levels downstream, Therefore can result in drought bc no longer receives the same amount of water.

What are vulnerable areas to sea level rise?

River deltas eg Nile and Bangladesh London and Netherlands (already at risk)

How may cold ocean currents cause aridity?

Run along coast cooling the air making it harder to hold moisture. Moisture falls as rain before reaching the land.

Describe the temperature variation across the UK in winter.

Sea warmer than land so heats up coastal areas. Higher upland areas experience colder temperatures. North Atlantic Drift means south-east remains relatively warm compare to others. Scotland and northern areas closer to polar cell and regions meaning they get more of cooler air.

How does the prevailing winds in reference to the UK's location influence its climate?

South westerly winds bring warm and wet conditions.

Describe the temperature variation across the UK in summer.

Summer sea cooler than the land so cools down coastal areas. Lack of altitude/highland means no temperature influence. Higher percentage of urban areas in south east warmer in summer. Maritime influences from med cause more warming.

What is weather ?

The day to day variation or change in atmospheric conditions.

What would happen if we did not have global atmospheric circulation ?

The equator would be intensely hot and the poles would be intensely cold.

What is the Coriolis Effect?

The gravitational forced exerted on the earth as it spins leading to winds moving anticlockwise in northern hemisphere and clockwise in the southern hemisphere.

How do global circulation cells and ocean currents transfer and redistribute heat ?

Via the Coriolis effect.

Describe the rainfall pattern throughout the UK.

WEST SIDE OF UK (NW-Scotland, Lake District, Cambrian mountains & Wales) more mountainous get more rain due to maritime influences from polar regions and Atlantic have large expanses of sea to build up moisture that dumped on high western areas of Britain. Forming relief rainfall patterns across those areas and shadow areas in the east.

How can agriculture lead to drought?

Water taken to irrigate farming land or pumped water from groundwater or rivers. May lower water supplies and worsen effects of drought.

Why is the Gulf Stream so important for biodiversity and climate in Europe ?

Without it we would be much 5-10 degrees colder. We would have longer winters and sparse ice covered landscapes in Europe.

What is the Coriolis Effect at the equator?

Zero