Water cycle TEST Flashcards
what percent of water on earth is stored as freshwater
2.5%
what percent of water on earth is stored in the oceans
96.5%
what is a closed hydrological system
one where there is a fixed amount of water on the Earth and atmosphere system
how long can water stay in the atmosphere as clouds for
10 days
how much water does the Sun evaporate every day
1 trillion tonnes
what are fluxes
how water is transferred between stores
how much ocean evaporation is there
413km^3 x 10^3 /year
how much ocean precipitation is there a year
373km^3 x 10^3 /year
what are the two processes that drive the hydrological cycle
solar energy and gravitational potential energy
how does the water budget limit the water available for consumption
through fossil water and cryosphere losses being non-renewable
what are the three types of rainfall
frontal rainfall, convectional rainfall, orographic rainfall
what is frontal rainfall
as air rises it cools and its ability to hold water vapour decreases, condensation occurs and clouds and rain form, this happens when warm and lighter air is forced to rise over cold, denser air
what is convectional rainfall
if the air continues to rise the rain will fall. When the land becomes hot, the air above it becomes warmer, expands an rises, condensation occurs and clouds develop, as it rises, the air cools and its ability to hold water vapour decreases
what is orographic rainfall
as the cloud forms, precipitation occurs, the leeward (downwind) slope receives relatively little rain, which is known as the rain shadow effect, when air is forced to rise over a barrier (such as a mountain), it cools and condenses
what is the river basin/river catchment area
the area of land drained by a river and its tributaries
what is watershed
the boundary of a drainage basin, this is usually a ridge of high land which divides and separates the water flowing different rivers
what are the human factors that affect drainage basins
deforestation, changing land use and over abstraction
between what years did the Tocantins river show increase discharge that coincided with increases rates of deforestation in the area
1960 and 1997, it showed a 25% increase in discharge
which UK cities suffered floods in 2014
Winchester and Maidenhead
what percent of London’s water comes from chalk aquifers
40%, the rest comes from the river Thames which is home to 13 million people
how much of the Amazon forest has been deforested
20% over the past 50 years
how much of the world’s rainforests does the Amazon contain
60%
in a forest how much of intercepted water is returned by evapotranspiration to the atmosphere
75%
water budget definition
a calculation of how much water there is in an area, it is important as it makes sure that people don’t die of dehydration
how long is the Nile
6,000km
how many countries does the Nile cross
9
what are three examples of impermeable rock
slat, marble and granite
what are three examples of permeable rock
sandstone, chalk and gravel
what is the definition of a flood
when a river exceeds its banks full discharge
example of snowmelt in the UK
Norfolk 2013, very mild and wet weather caused rapid thawing, which combined at the same time as heavy rain, causing local floods
example of monsoon rainfall
occurs across South and Southeast Asia between May and September, for example, in July 2016 the Philippines experienced heavy monsoon rains leading to flooding, landslides and evacuations in villages northwest of the capital Manila
storms and flash flooding example
intense, torrential storms are often associated with the UK during summer months, storms cause the capacity of the river to be overwhelmed quickly, for example in September 2016 flash flooding caused travel chaos as almost half a month’s worth of rain fell within hours in some places
what are the human causes of flooding
over farming, mismanagement of rivers and changing land use
example of mismanagement of a river causing flooding
2015, the River Greta in Keswick rose by 5.9 metres, breaching the raised riverbanks, there had been no dredging
what are the four different types of drought
meteorological, agricultural, hydrological drought, socio economic drought
what is meteorological drought
defined by shortfalls in precipitation because of short term variability within the longer term average overall, as shown in many semi-arid and arid regions such as the Sahel
what is agricultural drought
some farming practices such as overgrazing can accelerate the onset of this type of drought, Rainfall deficiency leads to deficiency of soil moisture and water availability which has a knock on effect on plant growth and reduces biomass
what is hydrological drought
occurs when there are deficiencies in stream flow and groundwater levels, which decreases because of a reduced inputs of precipitation and high rates of evaporation
what is socio economic drought
occurs when the water demand for social and economic purposes exceeds water availability. This could be a result of a weather-related shortfall in water supply or the overuse of the available water supplies. It is different from the other types of drought as it is dependent upon spatial variations in supply and demand
what is the ITCZ
Intertropical convergence zone, a belt of low atmospheric pressure located around the equator and moves North or South of it seasonally, high Sun intensity so high rates evaporation, in some world regions it causes a wet season when it arrives and a dry season when it leaves, sometimes the Hadley cell block the air masses preventing the arrival of the wet season causing drought
what is atmospheric circulation
Hadley cell, Ferrell cell, Polar cell
what are mid-latitude blocking anticyclones
high pressure systems that can block the movement of weather systems and cause extreme weather events, they bring stable weather with very little precipitation (often heatwaves), causing a drought in areas such as the UK which can persist for up to two weeks
what is the El Nino effect
naturally occurring large mass of very warm seawater in the equatorial Pacific Ocean, warm water in the western Pacific is usually pushed by ocean currents and trade winds, however every 7 years these pushing forces weaken which allows the mass of warm water to move eastwards towards the West Coasts of central and South America, the mass of warm water brings higher evaporation and precipitation, while to cooler areas bring drier weather
drought definition
a ‘shortfall’ or deficiency of water over an extended period of time
what are the two drought case studies
Pantanal Wetland, South America and Pinon Pines, South-West USA
what were the impacts of the 2014-2015 Pantanal Wetland drought
increased tree mortality and wildfires set by farmers that spread out of control
What were the impacts of the 2000-2003 Pinon Pines drought
made the trees more susceptible to pine bark beetle attacks, in some areas more than 90% of the Pinons died
in 2015 what percent of world’s people did not have reliable access to safe water and what percent lacked clean sanitation
15%, 25%
what percent of the volume of water is available as fresh water for humans to use
2.5%
water stress definition
water availability is between 1000-1700m^3 per person
water scarcity definition
water availability is between 500-1000m^3 per person
water security definition
sustainable access that is safeguarded and can sustain livelihoods and socio-economic development for ensuring protection against water borne pollution and water-related diseases
what is saltwater encroachment
when freshwater underground is replaced by saltwater due to there being too much groundwater abstraction, accelerated by climate change
what are the physical causes of water insecurity
climate, topography and distance from the sea, river regimes, geology
what is an example of climate causing water insecurity
The Sahel region in Africa, seasonally 85% of mean annual rainfall is in the summer, annually there is a huge variability due to warm sea surface temperatures that weaken the West African monsoon and contributes to drought
what is an example of topography and distance from the sea affecting water insecurity
the Himalayas where climate warming has led to widespread melting, diminishing the cryosphere and threatening water supplies of 500 million people in several countries such as Thailand, Vietnam and China
what is an example of river regimes affecting water insecurity
the Amazon river has an average annual discharge of 175,000 cubic metres per second from its catchment of nearly 7 million km^2 shared by Brazil and six other South American countries, sever droughts in 2005 and 2010 had a huge impact on Brazil’s water supply
what are human factors affecting water insecurity
quality and quantity
what are the China examples of Quality affecting levels of water insecurity
in China 300 million people use contaminated water daily and 190 million suffer from water-related illnesses annually, one third of all the rivers are classed as highly polluted, 2 million people may suffer from water-related diseases including Guandong province where liver and digestive cancers were responsible for 90% of recent deaths
what are the Bangladesh examples of quality affecting levels of water insecurity
nearly 20% of tube wells sunk in Bangladesh, often concentrated in particular villages, were found to be unsafe because of high concentrations of arsenic which can lead to major health problems such as cancer,
what are the examples of quality affecting levels of water security
Agriculture is the human activity with the largest water use- 70% globally and 90% in developing countries, freshwater withdrawals for energy production account for 15% of the world’s total
how many people worldwide have some signs of arsenic poisoning from drinking water
137 million in over 70 countries
how many people around the world have no access to sanitation facilities
2.5 million
what are the two flood case studies
Japan 2018, Nigeria 2012
what caused the 2018 Japanese flood
successive heavy downpours in southwestern Japan
how many people were advised or urged to evacuate in the Japan 2018 floods
8 million across 23 prefectures
how many members of the Japan Self-Defence Force police and firefighters searched for the people trapped or injured
54,000
how much rain were some areas hit by in the Japan 2018 floods
39 inches
how many homes were without electricity in the Japan 2018 floods
11,200
what was the total damage of the 2018 Japan floods
US$9.86 billion
how many people were killed and displaced in the 2012 Nigeria floods
363 people, 2.1 million
how many people in total were affected by the 2012 Nigeria floods
7 million
why does Nigeria suffer floods
during its annual rainy season, which are sometimes lethal, especially in the overcrowded slums where drainage is poor or doesn’t exist
how many health clinics and hospitals were destroyed
20 health clinics and 5 hospitals
what is the water poverty index
a measurement of the degree of water-related poverty in a region, country or community, it has five measures that are resources, access, capacity, use and environment
what are examples of potential conflict over water
The Great Ruaha River Tanzania and the River Nile
what is the name of the dam in the River Nile that opened in 1902
Aswan Low Dam
how much electricity will the Grand Ethiopian Renaissance Dam produce once built
16,000 GW a year
what percent of Egypt’s freshwater comes from the Nile
97%
what are the impacts of filling the Grand Ethiopian Renaissance Dam downstream
increased famine and thirst in Egypt and less water for agriculture
how many jobs will the Grand Ethiopian Renaissance dam provide
250 million
what is the example of a desalination plant
Veolia (France)
what are examples of sustainable management of water
rain water harvesting jars Kitayita village in Ethiopia, sustainable water management schemes in Singapore, Smart irrigation in China and Australia
what are the capacity of the rainwater harvesting jars
1,500 litres
what are the positives of the rain water harvesting jars
long life and made of locally available materials, close to home so remove the need for long distances to be travelled to get water
how much rainfall does Singapore receive a year
2,400mm per year
how does Singapore sustainably manage its water
collects rainwater through a network of drains, canals, rivers and reservoirs before it is treated, imports water from Malaysia, high grade recycled water
what is smart irrigation
provides crops with a suboptimal water supply causing mild stress during crop growth stages that are less sensitive to moisture deficiency, conserves water without a significant reduction in yield, increases water productivity by 60%
how much will China’s South-North Transfer project cost
US$100 billion
how long will the three canals in China’s South-North Transfer project be
1300km
how much water will China’s South-North transfer project transfer
44.8 billion cubic metres per year
