Climate change Flashcards
How does climate affect biodiversity?
It affects the abundance and distribution of virtually all organisms
How are ectotherms affects by climate?
environmental conditions directly determine their growth and developmental rates
Define latitudinal?
relating to the position of a place north or south of the earth’s equator.
Describe the 3 climates of latitudinal scale?
polar; ; considered stable as consistently cold
temperate; big seasonal fluctuations, very variable
tropical; 12;12 daylight all year round not much seasonal fluctuations,
What is the correlation between altitude and heat?
The higher the altitude, the colder it is and more variability
Name one the most variable habitats
Antarctic
Describe climate of alpine areas
high variability due to altitude
What type of organisms is spatial scale more relevant to?
ectotherms because teh spatial scale is much smaller and there are huge differences over very narrow spatial scale
What are ectotherms?
an animal that is dependent on external sources of body heat.
What are Milankovitch cycles?
Milankovitch cycles describe the collective effects of changes in the Earth’s movements on its climate over thousands of years. Including precessions, tilt on axis and eccentricity.
Describe the greenhouse gas effect
warming of the earth’s surface by greenhouse gases that allow solar radiation to reach the surface but delay passage of energy from the earth back to space
Why is solar radiation so important on earth?
It powers the climate system
- about half is absorbed by the earth’s surface and warms it
- some is reflected back into space
Describe how solar radiation reaches earth
short wavelengths
Why do wee need the greenhouse effect?
because without it, upward radiation from earth and incoming solar energy would reach a balance of only -18 degrees which is too cold
so this effect keeps teh earth’s temperature warm enough for organisms to survive
Why is a bad thing for greenhouse gas effect to increase?
-because a new balance is reached at a higher temperature leading to global warming, greater variability and closer to tolerance limits of certain species or ecosystems
Thermohaline circulation is a knock off effect of global warming. What is the thermohaline circulation?
they are deep ocean currents driven by differences in the water’s density controlled by temperature and salinity
Why are ice cores used for historical records of climate change?
- they let us go back a significant amount of time and shows changes in CO2 and temperature
How do you use ice cores to show climate change? (3)
- measure co2 directly from the air bubbles in the ice
- the isotopic balance gives an idea of temperature
- the ice encloses a small bubble of air which contain a sample of the atmosphere
What have the Antarctic ice cores shown us? (2)
that the concentration of CO2 was stable over the last millennium until early 19th century when it started to rise
- its concentration now is 40% higher than before industrial revolution (due to deforestation ad co2 emission)
Why are polar regions the most at risk from an increase in temperature?
-only takes a small increase in temperature to tip above 0 which means no freezing, no accumulation of snow and ice which has many knock on effects including ocean currents
Describe a cloche
- a mini greenhouse system
- limited control over extent of warming or other parameters
- useful in polar or alpine regions with no electricity
Name 3 disadvantages of cloches
- prevent colonisation of new species
- prevent visitation by predators, pollinators etc
- restricted to short vegetation and associated fauna
What are the key effects of climate change on a cloche in Signy Island?
- increase in temp causes increase in development rate and abundance of arthopods
- they get through life cycle quicker and produce more offspring
- creating more young animals but no change in biodiversity
What are arthopods?
invertebrate animals of the large phylum Arthropoda, such as an insect, spider, or crustacean.
What were the effects of the cloche in Anvers island?
- UV increase leas to decrease in species
- temperature lead to decreases in species, linked with more desiccation, habitats drying out
- water amendment lead to increases in species
Describe solar domes
- a way of stimulating climate change
- a greenhouse with control of CO2, temperature and moisture
- control over nutrient and water levels
Name 3 ways of stimulating climate change in isolated systems
- cloche systems
- solar domes
- ecotrons
Describe ecotrons and its benefits
a series of controlled environmental rooms, bringing ecosytems into the lab
- allows trophic interactions
- balance between looking at individual plants and understanding its ecological role
What does FACE stand for?
Free
Air
CO2
Enrichment
Describe how a FACE system works?
- it is a realistic simulation of future CO2 concentration
- no constraints by enclosures
- all factors remain normal (not controlled)
Name a limitation of FACE
Organisms are mobile so are constantly moving in and out of teh system, it is unclear how much time is spent in and how much time is spent out
Describe the purpose of BiFor
a decadal experiment to study the response of a mature temperate deciduous forest ecosystem to elevated CO2
Name the 3 main factors that need to be considered when looking at implications of climate change
physical systems (ice, permafrost, rivers..) biological systems (terrestrial ecosystems) Human and managed systems (food production)
Name the main abiotic impacts of climate change (4)
- glacial retreat
- flooding
- anoxic soil conditions
- drought
Name the main biotic impacts of climate change (4)
- phenological relationships
- shift in phenology
- shift in range margins
- alien/invasive species
What are the implications of glacial retreat?
- changes time and extent of meltwater
- impact on multiple systems dependent on this meltwater
- flooding
Why are anoxic soil conditions an impact of climate change?
- flooded soils can prevent efficient gas exchange between roots and soil,
How are anoxic soil conditions problematic?
under anaerobic conditions they increase soil PH (more alkaline)
- impact of microbiota-shift towards species that flourish under anaerobic conditions
- potential long term impacts on nutrient cycling and soil structure
Describe the effect of climate change on seasonal temperatures?
- minimum temperatures have increased more than maximum temperatures
- winters are milder
- extended the warm growing season in high latitudes
How are droughts caused due to climate change?
- changes in glacial melting times
- if the burst of meltwater is earlier than expected, later in the year these alpine areas can get dry
- elevated temperatures in alpine areas leading to drought
Name some ‘bioindicators’ of climate change
- Altered phenology (earlier occurrence of spring event e.g. bud burst on trees)
- northerly migration of species
Define synchrony and how climate change will change it
- the simultaneous appearance of 2 separate events
- climate change will lead to a loss of synchrony
Whats the difference between multivoltine and univoltine
multivoltine= many life cycles per year univoltine = one generation per year
What is diapause?
the period of suspended development in an organism especially during unfavourable environmental conditions.
How are alien species an impact of climate change?
A non native species arriving and colonising an establishment in an environment they were previously unable to as conditions weren’t favourable but now are able to cope
Define alien species
a non native species that adversely affects the habitat it invades economically environmentally or ecologically
Why is ANtarctica refrain from invasive species?
- because its so isolated by distances and also oceanic currrents that circulate so not as much marine accumulation creating a barrier to things reaching teh continent
