Geography Water Cycle

• During the 2015/2016 El Nino national temperatures in Australia reached 0.87 degrees above average
• Name 3 effects of the 2015/2016 El Nino in Australia

  • Low rainfall during growing season which led to crop failure
  • Water restrictions
  • Wildfires caused by drought destroyed vegetation and habitats
• During the 2015/2016 El Nino severe winter storms brought high levels of precipitation in California
• In California 45.7 metres of sandy beaches was eroded during the 2015/2016 El Nino
• In 2015 in preparation for the next El Nino, flood insurance in California increased by 30%
• An anti-cyclone blocker in 2014-2015 (meteorological cause) stopped rain from falling in the Amazon Basin, causing drought in Brazil
• During the 2014-2015 drought in Brazil there was water rationing for 4 million people
• The 2014-2015 drought in Brazil depleted 17 of the largest reservoirs
• Rainforests recycle 50-75% of their rainfall and drought reduces a rainforests ability to regenerate. Thinning forests have reduced soil water storage and evapotranspiration.
• Over-abstraction (human cause) also contributed to drought in Brazil because water companies tried to maintain water supply for factories and services
• High fees for drilling wells ($35,000-$100,000) caused many people to drill illegal wells
• Over 25,000 licences were allowed to drill but this was only 30% of the total number
• 70% were illegal wells which were shallower and less filtrated by bedrock so they contain industrial pollutants
• 1/10 of species on Earth lives in the Amazon
• The Amazon regulates the entire planets atmosphere
• Deforestation in the Amazon: 25,000km2 a year
• The Pantanal is the largest freshwater wetland (inland floodplain Brazil, Bolivia, Paraguay)
• Seasonal rainfall in the Pantanal brings water which is released slowly during the dry season, benefiting millions of people in the area
• Deforestation in the Amazon threatens rainfall in the Pantanal
• 74% of surface water of the Pantanal is already gone
• 90% of the Sahel's rainfall (100mm-600mm per year) falls between July and September
• Sahel: In the 1970s-1980s rainfall declined by 40% which caused drought, poverty and civil war in Eritrea and Ethiopia
• Sahel: Since 1996 several wet years opens up the possibility for re-greening
• Re-greening is a restoration technique that involves planting trees and bushes (popular in Malawi, Ethiopia and Niger)
• California: 40 million people are at risk due to a lack of rainfall
• California: Droughts are normal features in Californian climate, but they have been getting more intense with 3x more wildfires
• Water Scarcity: an imbalance between balance and supply
• Water stress: there is less than 1700m3 of water available per person per year
• Agriculture is the largest use of water, consuming 70% worldwide
• 20% of world aquifers are over-exploited (over-abstraction)
• In 2015, 1.35 million m3 of contaminated water was released into the Animus River from mining operations
• 1/2 of the worlds population now lives in urban areas which puts more stress on these areas
• 1/3 of the population in Asia lacks access to safe drinking water
• 25 African countries will face either water stress or scarcity by 2025
• Only 2% of sewage is treated and made drinkable in Latin America
• California: In Spring 2021 annual winter rainy season failed to replenish the hot landscape and a hot summer took even more moisture from the land
• California: In May 2021, 93% of the south-west and California was in drought
• California: Heat has been changing the water cycle which means less snow will fall, of which California relies on for 30% of its water supply
• California: Drought disasters has caused $9.3 billion in damage in recent years
• California: Dry conditions have fuelled wildfires engulfing 4.1 million acres in 2020 and killing 31 people