Geography Unit 1, World at risk

Weather Patterns
1. El Niño
  1. El Niño is a climate pattern that describes the unusual warming of surface waters along the tropical west coast of South America. El Nino has an impact on ocean temperatures, the speed and strength of ocean currents, the health of coastal fisheries, and local weather from Australia to South America.
  2. Occurs every 2-7 years
  3. Effects on places
    1. South America
      1. Because El Niño's warm pool feeds thunderstorms above, it creates increased rainfall across the east-central and eastern Pacific Ocean, including several portions of the South American west coast. The effects of El Niño in South America are direct and stronger than in North America. An El Niño is associated with warm and very wet weather months in April–October along the coasts of northern Peru and Ecuador, causing major flooding whenever the event is strong or extreme.
      2. El Niño reduces the upwelling of cold, nutrient-rich water that sustains large fish populations, which in turn sustain abundant sea birds, whose droppings support the fertilizer industry. The reduction in upwelling leads to fish kills off the shore of Peru.
        During the 1982–83 event, jack mackerel and anchovy populations were reduced, scallops increased in warmer water, but hake followed cooler water down the continental slope, while shrimp and sardines moved southward, so some catches decreased while others increased. Horse mackerel have increased in the region during warm events. Shifting locations and types of fish due to changing conditions provide challenges for fishing industries. Peruvian sardines have moved during El Niño events to Chilean areas.
    2. Indonesia and Australia
      1. As warm water spreads from the west Pacific and the Indian Ocean to the east Pacific, it takes the rain with it, causing extensive drought in the western Pacific and rainfall in the normally dry eastern Pacific. Singapore experienced the driest February in 2014 since records began in 1869, with only 6.3 mm of rain falling in the month and temperatures hitting as high as 35 °C on 26 February. The years 1968 and 2005 had the next driest Februaries, when 8.4 mm of rain fell.
      2. Droughts to Indonesia and Australia. These droughts threaten water supplies, as local reservoirs dry up and rivers carry less water. Agriculture, which depends on water for irrigation, is threatened.
      3. See Phillippines case study
    3. North America
      1. See California Case Study
  4. The El Niño event of 1997-98 is regarded as the strongest of the 20th century. This was the first El Niño event to be scientifically monitored from beginning to end. The 1997-98 event produced severe drought conditions in Indonesia, Malaysia, and the Philippines. Peru experienced very heavy rains and severe flooding. In the United States, increased winter rainfall hit California, while the Midwest experienced record-breaking warm temperatures during a period known as "the year without a winter."
    1. By the time it had run its course eight months later, the giant El Niño of 1997-98 had deranged weather patterns around the world, killed an estimated 2,100 people, and caused at least 33 billion [U.S.] dollars in property damage.
    2. The mosquitoes that thrived in these places caused rampant malaria—some 30,000 cases in the Piura region alone, three times the average for its 1.5 million residents.
      1. The Piura region is in North West Peru
    3. Temperatures reached 108°F [42°C] in Mongolia; Kenya’s rainfall was 40 inches [100 centimeters] above normal; central Europe suffered record flooding that killed 55 in Poland and 60 in the Czech Republic; and Madagascar was battered with monsoons and cyclones. In the U.S. mudslides and flash floods flattened communities from California to Mississippi, storms pounded the Gulf Coast, and tornadoes ripped Florida.
  5. In addition to increased natural hazards and economic devastation, health crises are also associated with El Niño events. Diseases carried by mosquitoes and flies, such as dengue fever and malaria, increase as warmer, more humid weather expands mosquitoes habitat.
2. La Niña
  1. There are occasions when the trade winds that blow west across the tropical Pacific are stronger than normal leading to increased upswelling off South America and hence the lower than normal sea surface temperatures. The prevailing rain pattern also shifts farther west than normal. These winds pile up warm surface water in the West Pacific. This is the cool phase of ENSO called La Niña.
  2. Effects
    1. Generally, the Opposite of an El Niño year
    2. La Niña is characterized by lower-than-normal air pressure over the western Pacific. These low-pressure zones contribute to increased rainfall.
    3. However, strong La Niña events are associated with catastrophic floods in northern Australia. The 2010 La Niña event correlates with one of the worst floods in the history of Queensland, Australia. More than 10,000 people were forced to evacuate, and damage from the disaster was estimated at more than $2 billion.
    4. Rainfall associated with the summer monsoon in Southeast Asia tends to be greater than normal, especially in northwest India and Bangladesh. This generally benefits the Indian economy, which depends on the monsoon for agriculture and industry.
    5. La Niña usually has a positive impact on the fishing industry of western South America. Upwelling brings cold, nutrient-rich waters to the surface. Nutrients include plankton eaten by fish and crustaceans. Higher-level predators, including high-value fish species such as sea bass, prey on the crustaceans.
    6. La Niña events may last between one and three years, unlike El Niño, which usually lasts no more than a year. Both phenomena tend to peak during the Northern Hemisphere winter.
  3. Scientists use the Oceanic Nino Index to measure the deviations from normal sea-surface temperatures that El Niño and La Niña produce in the east-central Pacific Ocean. La Niña events are indicated by sea-surface temperature decreases of more than .5 degrees Celsius (.9 degrees Fahrenheit) for at least five successive three-month seasons.
3. Extreme weather
  1. Distribution
    1. Including hurricanes (North America), cyclones (India) and typhoons (Japan and East Asia). They all occur in a band that lies roughly between the tropics of Cancer and Capricorn and despite varying wind speeds are ferocious storms. Some storms can form just outside of the tropics, but in general the distribution (location) of these storms is controlled by the places where sea temperatures rise above 27°C. The highest number of storms does not occur in the Atlantic close to the USA, but in the North Pacific affecting countries such as the Philippines and Japan. This is despite the fact that in the UK we only really get to hear about tropical storms affecting the USA. The most affected area being South East Asia receives an average of 26 storms per year. The least affected area is India where there is an average of 2 tropical storms per year.
    2. Equatorial belt, 5-20 degrees north and south of the equator
  2. Conditions
    1. Ocean temp over 27 degrees
    2. At least 50m water depth
  3. Hurricane Jeanne
    1. Winds estimated to be 193 km/h
    2. Category 3 on Saffir-Simpson scale
    3. The most severe impact from Hurricane Jeanne was the immense rainfall it produced. The Caribbean islands saw extreme amounts of precipitation and the consequences were deadly. At Vieques, Puerto Rico, 610 mm (24 in) of rain fell. Historic flooding occurred throughout the island causing $169.5 million (2004 USD) in damage but only claiming 8 lives. In Haiti, 330 mm (13 in) fell over the northern mountains producing catastrophic mudslides. Over 3,000 people died as a result, with almost 2,900 of them perishing in the coastal city of Gonaïves. Over two dozen people were killed in the neighboring Dominican Republic after rainfall led to flooding there as well. 12th deadliest Atlantic hurricane on records.
The Arctic
1. Climate Change
  1. Rising sea levels
  2. Melting Ice Caps has resulted in loss of habitats and disruption of ecosystems
  3. The Greenland Ice Sheet
    1. Huge levels of sea level rise
    2. Caused by the emission of greenhouse gasses and environmental pollution increasing sea and air temperatures
    3. From 1979 to 2006, summer ice melt has increased by 30%
    4. This has opened trade routes for shipping thus adding to oil and shale gas exploration. This is only worsening the situation as the oil rigs create even more greenhouse gasses and add to the effects of global warming
  4. Thermal expansion
2. Spruce Bark Beatles are eating Alaskan forests. From 1993 to 2003 over 3.4 million acres of forest was eaten.
3. Sea Ice Melt
  1. Resulting in loss of habitat for polar animals e.g. polar bears and seals which use the ice to hunt. This could lead to a reduction in biodiversity which is detrimental to the whole ecosystem.
  2. More ice melting results in less albedo affect as the suns light reaches more of the ocean which absorbs it rather than the ice reflecting it back. This leads to exponential increase in the sea ice melt as the more ice that melts the more suns radiation is absorbed and further sea level temperature increase takes places.
  3. Low lying countries such as Bangladesh are at extremely high risk of flooding from sea level rise and as a poor country the effects of flooding will be catastrophic.
  4. The Netherlands is a very low lying country which is at a very high risk of flooding due to sea level rise however as a wealthy MEDC the capacity to cope with these hazards is far greater than poor nations such as Bangladesh.
  5. London is also a low lying city however as the capital city of a wealthy country it has money in order to spend adapting to sea level rise. A good example of this is the Thames Flood Barrier.
  6. At current rates 50% of Arctic ice will be lost by 2100
  7. The arctic ecosystem is highly vulnerable as it is deeply adapted to an intense, seasonal climate. It relies upon a continuous, very cold winter.
    1. There is evidence that this winter is fast disappearing to be replaced by more variable cold-thaw conditions whichlead to iceing, fails to kill pests, and promotes waterlogging.
4. 6-8 degrees warming by 2100 considered a distinct possibility
The Phillippines
1. 7,107 Islands
  1. Only about 2000 inhabited
  2. Very difficult to access everyone in case of a disaster
2. Situated on the western fringes of the Pacific Ring of Fire, the Philippines experiences frequent seismic and volcanic activity. The Benham Plateau to the east in the Philippine Sea is an undersea region active in tectonic subduction. Around 20 earthquakes are registered daily, though most are too weak to be felt. The last major earthquake was the 1990 Luzon earthquake.
3. Earthquakes
  1. Sits on destructive plate boundary
  2. The Luzon earthquake
    1. July 16 1990
    2. 7.8 magnitude
    3. 500 dead
    4. Lots of the surrounding area was rural so less vulnerable
      1. Less debris, electrics, gas (reduced risk of aftershock damages)
4. Volcanoes
  1. The Pacific ring of fire
  2. Oceanic Phillippines plate is subducting under the Eurasian plate at 16cm per year
  3. 37 volcanoes, 18 active
  4. Mount Pinatubo
    1. 15th June 1991
    2. 700+ killed
    3. $500,000,000 property damage
    4. Cyclone Yunya followed causing major rainfall and lahars which resulted in more deaths
5. Drought
  1. Climate is 25-28 degrees, during El Nino hot and dry
    1. Wildfires
  2. 1997-98 El Nino
    1. 2,600,000 people affected
    2. Farmers only got 30% of normal income
    3. 72 dead due to stagnant water
    4. 90% of the country got below 50% average rainfall
California
1. Earthquakes
  1. Conservative and destructive boundaries on the northern end of California
  2. San Andreas Fault line, conservative plate boundary
  3. Loma Prieta
    1. 17 October 1989
    2. 7.1 on richter scale
    3. 63 deaths
    4. $6 billion damages
    5. 1,018 homes destroyed
2. Drought
  1. Caused by high pressure, anti-cyclonic conditions
  2. Santa Ana winds bring dry wins down from death valley. Stops low pressure and the weather which comes from low pressure
  3. Drought 2013-2014
    1. July 1st 2013- January 13th 2014
    2. Received just 20% of normal rainfall (2.1 inches)
    3. 1/3 of all food made in USA is in California so this drought had major implication for food production. The human vulnerability is increased here therefore as the whole of the US is affected by droughts here.
    4. Resulted in 5059 fires across 90,375 acres of land
3. Wildfires
  1. 2012-2013
    1. Burnt over 600,000 acres of land
    2. 2012 $481.7 million spent fighting fires 2013 $599 million spent
    3. Winds fueled the fire further into towns and cities with the dense populations making impacts more extreme in these areas
Africa
1. Lowest contribution to global warming
2. Predicted temp change 4-5 degrees above global rate
3. More rain in equatorial band but less above and below
4. Water
  1. Regulated by HEP, domestic and industry
  2. Rivers shared e.g. Nile
    1. Conflict
5. Food insecurity
  1. 70% of population subsistence farmers who may starve with water shortages
  2. Increased locust plagues
6. Natural resources
  1. Loss of safari tourism industry in places like Kenya as the Big 5 wild animals will die out.
    1. In Africa, the big five game animals are the African lion, African elephant, Cape buffalo, African leopard, and White/Black rhinoceros.
  2. 80% of remedies rely on wild plants that are under threat.
7. Vector borne and water borne diseases could increase with climate change - higher medical expenses
8. Desertification
  1. Major destroyer of grassland
  2. Increased by unreliable or decreasing rainfall

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Geography Unit 1, World at risk

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	Criado por Jason Edwards-Suarez mais de 9 anos atrás