implications of CC Flashcards
what is an ecosystem
a community of plants, animals and other organisms that interact with the physical environment and each other through flows of energy and the cycling of nutrients
what does climate do to ecosystems
shapes habitats and supports plants and animals
how do species react to CC
some species adapt to climate change, others can’t and face decline and extinction
how does climate change affect marine ecosystems?
-Global warming raises sea surface temps
-call Reese threatened by bleaching caused by higher SSTs
-Death and bleaching of coral caused by small rise in SSTs (1-2*)
Example of how climate change affects marine ecosystems
-in the past 30 to 40 years, Indonesia has lost half of its reefs to bleaching
-caribbean lost 80%
how are marine ecosystems affected in the Arctic by climate change?
-Warming of the Arctic Ocean and shrinking of sea ice has decimated ice algae (base of marine food chain)
-Sea ice is crucial to survival of marine mammals such as walrus and seals
-This means a decline of polar bears
-A decline of sea ice projects a 2/3 decline in polar bears by mid century
how do walruses and ring and harp seals use sea ice
walrus-uses ice as diving platforms for foraging the sea bed and travelling long distances
-and harp seals use ice to rest, give birth, raise pups and moult
what human group relies on natural ecosystems
-indigenous inuit hunters of Arctic
how do the indigenous hunters of Arctic rely on natural ecosystems?
Their economy and culture depends on hunting, marine mammals, like walrus and seals
how does cc affect the inuit people
The melting and sinning of ice makes hunting dangerous
-More open water means more killer whales
-killer whales are natural predators of bowhead whales, narwhales, and seals
-killer whales are indirect competition with the hunters
how much have SSTs increased since 1980 in the UK
1.6*c
what does warming seas limit? and what happens as a result of
-Food supplies, growth rates and spawning for many fish
-as a result, indigenous Coldwater species, such as cod, haddock and mackerel have moved northward to Iceland and Faroe Islands
-and warm, more species like Seabass and hake have migrated into UK waters
-This has implications for the UK fishing industry as commercial fishing has to switch to new species and fishing for Coldwater fish shifts northward
what is vulnerability
defined by the ipcc as ‘ the extent to which a natural or social system is susceptible to sustaining damage from climate change’
what’s vulnerability a function of
the sensitivity of a system to changes in climate, adaptive capacity and the degree of exposure of the system to CC
what does vulnerability of CC depend on
-where they live
-their ability to cope
who are the most vulnerable
young, elderly and chronically ill are more vulnerable
who will and increase in droughts hit the hardest?
farmers in marginal farming environments, where rainfall is only just sufficient to support agriculture
example of somewhere affected by increased drought
-Sahel- Northern Africa
-since 1979, crop and grazing land was abandoned due to severe land segregation and desertification as a result of over-cultivation and excessive exploitation of soil, water and pasture resources
what does increased drought cause a decline in
cereal yields will could eventually lead to global food shortages
what % of the worlds glaciers are retreating
90%
who will experience water shortages as a result of glacier retreat
regions that rely on glacial meltwater for irrigation will experience water shortages
what populations are vulnerable to flooding
populations in low lying coastal regions in the tropics and subtropics
-floods from rising sea levels and tropical storms
what impact do storm surges have on people and the environment
-loss of life
-destroy crops
-kill livestock
-leave a legacy of salanised soils
-contaminated water supply
who are at risk from heatwaves
urban population
why are people who live in poverty and greater risk
they have the fewest entitlements to protect themselves
what is mitigation
IPCC defines as ‘a human intervention to reduce the sources or enhance the sinks of GHG’
what’s adaption
a strategy to minimise the impact of CC today
-used when threats to ppl and environment require immediate action
how are tundras affected by CC
-rising temps melt permafrost
-this disrupts vegetation and creates extensive thaw lakes and wetlands
-this initiates mass movement
-forests will invade southern margins of tundra
how are mountainous regions affected by CC
-glaciers retreat
-makes slopes less stable = mass movement.
-snowline will recede upslope and winter snowpack will thin
-reduces meltwater into rivers
how are hot semi-arid conditions affected by CC
-rainfall becomes more erratic
-rainy season will shorten
-droughts will increase in length and frequency
-less vegetation cover and drier conditions increases wind erosion and dust storms
how are rainforests affected by CC
-as deforestation increases the water cycle weakens
-creates positive feedback and accelerates forest loss
-30-60% of amazon rainforest could become dry savanna grassland by end of the century
how are coasts affected by CC
-higher sea levels and more powerful storms increase erosion rates in both upland and lowland coasts
-shorelines retreat inland
-dunes, salt marshes and mudflats at increased risk
what Increases in frequency and intensity with climate change
storms
droughts
heateaves
what do rising temps disrupt and what consequences does this have?
rising temps r known to disrupt the mid latitude and sub tropical jet streams
-increases evaporation and humidity and modifies pressure patterns both in the atmosphere and at the surface
example of how weather patterns have changed since 1970s
2005 hurricane season in North Atlantic Caribbean area produces a record breaking number of storms including category 5 hurricanes
what has happened to the frequency of hurricanes
hasn’t changed
stayed at around 90/yr
where r tropical cyclones found
tropics
sub tropics
mainly north atlantic and pacific oceans
western pacific
where r mid latitude depressions found
mid latitudes
between 35-70*
where r tornadoes found
continental areas in mid latitudes
eg/ midwest USA
where’s heavy rainfall found
widespread
most extreme in climates with wet and dry seasons
where r blizzards found
high latitudes and mountainous regions
where r severe cold spells found
mid-high latitudes
continental locations not oceanic
where r heatwaves found
mid latitudes in summer
where r droughts found
widespread but most common in sub-tropics (eg/ Sahel)
and continental interiors (midwest USA)
mediterranean
example of severe floods
somerset levels 2014
what r responses to flooding
hard engineering flood defences
managed land use changes to delay run off
what do tropical cyclones create and what do they threaten
create huge storm surges which threaten populations in low lying coastal areas
example of a place affected by a cyclone
bangladesh suffered a super cyclone in may 2020
-220000 homes destroyed
-left 500000 homeless
-damage estimated at US$ 1.5 billion
what do more frequent and powerful depressions cause
accelerated rates of coastal erosion in mid latitudes which will need more defences
-expensive
what threats do increased heatwaves pose to people
threat to human health, especially elderly in urban areas where HEAT ISLAND EFFECT is more intense
-greening urban areas promotes evaporation and cooling
what threats do droughts pose to people
leads to water shortages
-affects activities such as crop growing, ranching, river transport and power supplies
-failure of asian monsoon could lead to severe regional and global food shortages
what ecosystem are temperatures rising fastest
tundra
what happens as the permafrost thaws?
The wetland areas expand which attract migratory birds like wild foul and waders
whata happening to the breeding season as temperatures increase
The breeding season becomes longer and higher temperatures ensure an abundance of insects
how are terrestrial ecosystems affected by climate change?
-Southern fringes of tundra will lose open aspect as tree line advances north
-Forest replaces tundra, change in habitat will affect indigenous plant and animal species
-Migration patterns among Caribou will be disrupted
-as habitats shrink, predators which rely on lemming population will be forced Northward
what does a 1° C rise and temperatures require an uphill movement of
200-275m to maintain the same habitat
What is phenology?
The study of changes in the timing of spring and other natural seasonal events
is an indicator of global warming
how much has the IPCC predicted that spring has moved?
2.3-5.2 days earlier per decade
what does spring moving earlier cause?
A loss of synchronisation between species as animals awaken from hibernation or start to breed before the emergence of foods resources like leaves, insects, lavae and caterpillars
how many more deaths worldwide are they gonna be that linked to climate change between 2030 and 2050
250,000 deaths per year
linked to climate change and the spread of infectious disease, malnutrition and diarrhoea
what will climate change stimulate in relation to human health?
The transmission of vector-bourne diseases and their geographic range
An example of a disease spread by vectorborne have migrated
dengue fever is spread by the aedes mosquito and formally confined to the tropics and subtropics, but is today found in 28 US states
-temperatures and rising rainfall favoured the spread of mosquitoes, carrying the disease
what is climate change responsible for the spread of?
lymes disease in the USA
-Transmitted by ticks which thrive in warmer conditions, so expanding northwards
-They will eventually colonise Canada
What do increased floods do to human health?
pollute water supplies by human waste
-Bacteria in the water will multiply the risk of diarrhoea, which is a major cause of deaths in LIDCs
What does a reduction in crops yields and food production by increased droughts and flooding threaten
food security in human health with widespread malnutrition and under nutrition in LIDCs
-IPCC suggest significant reductions in staple cereal crops by 2030
