D4.3 Climate change

Methane and Crabon dioxide

• greenhouse gases

• carbon dioxide: buring of fossil fuels for elctricty

• methane: livestock and agriculture

• anthropogenit increase of those gases

Positive feedback loop of relase of carbon dixodide

• increased CO2

• surface water is warmer

• phytoplankton produces more biomass

• passed on to rest of teh food

• when those organissm die decomposers in the benthic zone (bottom od ocean) decompose creating more CO2

Positive feedback loop of increased solar radiation

• incraesed temparyure

• melting of ice

• coeans have lower albedo

• absorb more light

• heating up ocean

• even more melting

Positive feedback loop of decompostion of organic matter

• at low tempratures decomposers decompose at lower rate due to low enzymatic and metabolic activities

• climate change icnreases tempratures

• decomposers can decompose organic matter in peat bogs creating more carbon dioxide

• normally peat bogs are carbon sinks

Positive feedback loop of melting permaforst

• increased tempratures

• increased melting

• microbes become active and deocmpose the organic matter generating CO2

• also methanogenic archea whcih generate methane

• increasee greenhouse effect

Positive feedback loop of fires

• climate change causes warm

• drought

• causing fires

• even more CO2

Tipping point example

Borreal forest

• warmer tempratures → less snow

• less snow → less water for trees

• less water → less photosynthesis

• less photosynthsis and primary production → less CO2 removed

• trees become dry loose their green pigemnt → forest brownign

• drough can cause fires

• fires brun trees relasing all the CO2 stored in the trees and legacy carbon stored in the soil

• The forest switches from sink to source

• Tipping point: threshold that if reached causes massive changes ofetn irreversible

Emperor penguings

• Antarctica

• breed on landfast ice and wait for chicks to grow so they can find their own food

• with climate change the ice begins to melt earlier but the chicks are not ready yet

• Penguins need to move to ice on land → threat to their population

Walruses

• arctic

• also prefer landfast ice for habitat and breeding

• they can leave their young and dive into water for food

• with melting of ice they have a probelm as they moved poleward

• but need to live their young further and then go dive leaving the vulnerable to predators like poalr bearn which also have trouble finding food due to climate change

Ocean currents

• nutrint upewlling - surface water pushed down by wind and nutrint rich deep water pushed up to give nutrients to marine animals

• El NIno happens evere few year and there is no nutrint upwelling causing decreased primary production, less energy flow in food chains

• Climate change increases the severity of el Nino

Poleward range migration of trees

North America trees

• with climate change tempratures reduce allowing the trees to move and survive in the area

Upslope migration of birds

• Papua New Guinea - monatne bird species

• They prefer ceratin altitudes

• with incraesing tempratures usulaly migrate upslope as they prefer to be in their ideal temparture range

Example of ecosystem collapse

Coral reefs

• Increased CO2 concetration causes formation of carbonic acid which re3lases H+ ions reducing the pH → acidification

• The skeleton of coral reefs is formed from calcium carbonate but when exposed to acid it becomes dissolved prohibiting formation of desne stong corals

• Warmer tempratures causes coral to expel their smbiotic algae (zooxantehlelle) which provides colour and energy leading to coral bleaching and death of coral

• This will cause many marine animals to seek diffrent food sources and habitats

Carbon sequestration

taking atmospheric carbon and locking it somewhere

How to do it:

• reforestation

• afforestation

• restoration of wetlands

Phenology

timing of periodical events

Temprature and phenolgoy

• bud setting - requires warmth

• flowerirng promtoion - needs activation of enzymes

Photperiod and phenology

• bird migration

• bud burst

• flowering

Disruption of phenological events

Reindeer eat Artctic mouse-ear chickweed.

• Reindeers migrate using day lenght whereas the artic mouse ear grows as an effect of temprature

• With incraesed temprature due to global warming arctic mouse ear grows faster when the reindeer has not yet retuered causing a trophic mismatch

great tit and capilaries

• Great tits liek to feed capiallries to tehir young due to protein and easy digestion

• Days of when the chciks are redy to eat are the same but when teh capialries are ready to eat has gone down by a week

• also mismatch as teh capilaries are in a diffrent life cycle or harder to digest when chicks ar ready

Life cycle of insects

Spruce Bark Beetle

• burrwos under bark of spruce making tunnels to lay egegs

• the larvae then feed on the wood → can cause structural damge to tree even death

• Spruce bark beetles can prdicue one generation in a year (monovoltine cycle) or two (bivoltine cycle)

• Low tempratures are infavorable → only one cycle

• Increasing tempatrutes are more favorable → increase in life cycles

• More damages and dead trees

Evolution and climate change

Tawny Owl

• More brown morph than grey morph

• When there was more snow grey was less visible to preadators now with decraese natural selection favorus brown

• number of voles they eat also decraesed more availbel in autumn then winter