Climate Change: Hydrosphere & Atmosphere

Consequences of Global Climate Change

Effects on the Hydrosphere & Atmosphere

• Mean global temperature increases impact ecosystems and shifts precipitation patterns
• Higher greenhouse gas concentrations intensify extreme weather events like hurricanes and heavy rainfall
• Altered energy balance in Earth's atmosphere from long-term climate changes impacts weather patterns
• Thermal expansion of seawater and melting land ice due to greenhouse gases leads to sea level rise

Effects on water stores

• Temperature changes from the exchange of energy influences the hydrological cycle
• Evaporation cools the environment while condensation warms it, influencing local climate
• Reduced polar ice impacts polar ice and the albedo effect
• Ice melt releases fresh water into the oceans, altering the thermohaline pattern
• The thermohaline circulation relies on heavy salt water to transport water, carbon, and heat
• Large freshwater deposits can disturb or stall the ocean conveyor belt
• Dark oceans absorb more heat, boosting evaporation- a positive feedback loop
• Increased evaporation boosts cloud formation- a cooling effect (negative feedback)
• Higher temperatures increase humidity leading to more precipitation
• The atmosphere retains more moisture with higher temperatures

Changes in water availability

• Alterations in precipitation patterns can change water availability
• Some regions may have increased rainfall and floods, while other areas face frequent severe droughts impacting on agriculture, drinking water resources, and ecosystems

Sea-level change

• Thermal expansion of water and melting ice increases volume of water in ocean basins
• During the last Ice Age, sea levels fell, and rose again during the subsequent ice melt
• Greenland and Antarctica ice loss from 1992-2017, totaled 6.4 trillion tones causing a sea level rise of 17.8mm
• Ice sheets contribute to a third of sea level rise compared to 5% in the 1990s
• By 2100, polar temperatures could be 7°C above pre-industrial levels
• Sea levels have a significant affect on low-lying coasts and islands
• Pacific Ocean islands, such as Kiribati and Tuvalu are at risk of being submerged

Coastal flooding

• Coastal flooding and increased vulnerability to storm surges is due to rising sea levels
• Loss of land, infrastructure, and displacement of coastal communities can occur as a result
• Many of the world's densely populated areas are located on coastal lowlands
• New York and Miami are major cities vulnerable to sea-level rise
• Bangladesh is vulnerable because it's densely populated with a swamp forest

Carbon Stores

• Permafrost acts as a carbon sink of partially decomposed organic matter
• Melting triggers methane release as the plant/animal matter decomposes
• Methane is a potent greenhouse gas, creating a positive feedback loop
• There are 5 gigatons of methane in the atmosphere
• The Artic permafrost contains hundreds of gigatons of methane
• Polar ice sheets and glaciers are also stores of carbon

Impact of ice change

• Rising emperatures are causing ice melt across the world
• Glaciers in the Himalayas, Southern Alps, and Rockies are melting rapidly
• Ice melt releases freshwater for people living along rivers

Ocean acidification

• Oceans can absorb more atmospheric carbon and are important for regulating atmosphere

• Carbon is moved through the oceans in both directions

• Phytoplankton uses dissolved CO2 for photosynthesis

• Carbon is transported from the surface to the deep ocean levels

• Organisms sink and release CO2 into deep water stores upon death

• Some material transformed into rocks locks carbon into the long-term cycle

• Increased atmospheric CO2 causes higher CO2 absorption by oceans and leads to acidification

• Ocean acidification harms marine life, like coral reefs and shellfish

Carbon in the biosphere

• The biosphere acts as a large carbon sink
• CO2 is released naturally into the atmosphere through respiration and decomposition
• Humans release extra CO2 in the atmosphere
• Plants/Soils absorb 25% of human released CO2 through photosynthesis
• Too much atmospheric CO2 impairs plantgrowth and storage, and impacts crop yields
• Deforestation leads to CO2 release

Water cycle/carbon cycle feedback loop

• Water absorbs/transfers carbon with oceans absorbing 33% of CO2 emissions
• Oceans absorb most of human-generated CO2 although absorption has slowed
• Melting ice increases carbon storage, but is limited by dropping ocean pH levels which increase ocean acidification
• Warmer temperatures increase phytoplankton
• Phytoplankton releases dimethylsulphide (DMS), leading to increased cloud formation
• Insolation reduction reduces phytoplankton, which lessens cloud cover
• Rising ocean temperatures reduce photosynthesis in phytoplankton in cooler waters.
• Increasing ocean acidity impairs shell-forming marine creatures from extracting bicarbonate ions

Extreme Weather Events

• Changes in climate patterns increase the frequency & severity of weather events
• There has been an increase in extreme weather events Since the 1980s
• Floods, storms, and extreme temperatures are frequently occurring
• The Atlantic hurricane season lasts from June 1 - November 30
• Tropical storms commonly form in the North Atlantic during this time
• Annually 14(avg) named storms occur with six hurricanes (Cat 3), and 3 major hurricanes (Cat 4+)
• 2021 produced 21 named storms (winds of 62+ km/h), with 7 hurricanes (winds of 119+ km/h) of which 4 were major hurricanes (winds of 178+ km/h)
• Drought describes a period of below average rainfall
• Droughts vary from place to place with different vegetation
• Water supplies can be depleted as people abstract water during a drought
• Droughts are often accompanied by rising temperatures and water supplies are depleted
• Length of a drought varies with place
• UK suffered a drought for 16 months (1975-1976)
• In any given year, 14% of the USA is in drought
• The Horn of Africa is experiencing its worst drought in 40 years
• Changes in atmospheric circulation patterns affect precipitation in an area
• An El Niño cycle affects Australia and Indonesia causing droughts
• Weather system and high pressure systems cause rates of evaporation
• A heat wave is when temperatures are higher than average for a prolonged time (UK means 3 consecutive days)

Projected impacts of rising temperatures

Effects on the Biosphere

• Ecosystems play a role in carbon cycling
• The availability of moisture impacts with the animal distribution and importance of growth
• Changes in Temperature/ rainfall and habitat affects species survival patterns and interactions
• Conditions will improve crops and ecosystems, but others will suffer as an affect
• Move north/south because they need specific climate conditions
• Polar/Tundra biomes are at risk as they are move futher N/S
• Rising sea temperatures/ocean acidification has caused coral bleaching
• Migration/ behavior patterns has changed
• Longer distances to find cooler climates, reduced pests, diseases and predators
• Fish species are already moving N/S
• Reduced hibernation time as temperatures are increasing
• Migrations begin annual as birds leave and head north for summer
• Soil erosion reduces fertility because Rainfall/ low vegetation

Impacts on Agriculture

• Suitable areas will change in order for agriculture
• Farmers will change crops
• Areas will grow on areas not used
• Coastal flooding
• Water shortages, irrigation/ limits crops to be chosen
• Food shortages due to malnutrition and Famine
• A rise of 3°C would reduce crop yields to 35% (across Africa and the Middle East)
• A rise of 2°C(200 million) affect the cause of hunger

Effects on People & Places

• Loss of job opportunities due to changes in agriculture/tourism
• Coastal resorts risk as resorts will close because of lack of snow
• Farmers either change crop or leaving farmlands
• Floodings due to sea level rises will leads to displacement of large numbers of people

Homes

• Homes will need additional defences sea level rise
• Moving settlements or improving food levels
• Social migration and the increase of human migration with Lowed islands

Health Hazards

• Climate changes affect human in many ways
• Heatwaves ,weather events, disease negative/ health consequence, respiratory, spreading infectious disease
• Water-borne is spreading and is high in temperature
• Heartstroke
• Dehydration increases skin burns
• Pollution levels high
• Respiratory increased and suffer from asthma

Tourism & Transport

• Ocean transport which 90% of global trade
• Sea routes which 90% open ships will sovereign waters
• routes and the volume of sea vessels by shorter canals
• Arctic ice pack 2009 shipping between Atlantic over the year
• 40% shorter now
• Arctic environments will impact ships
• Egypt could use upto 60% loss