Climate change

Question 1

Examples of biome change due to climate

Answer 1

0 yr ago - lots of cool conifer forest, open conifer woodland, and some desert
18000 desert north, and only open conifer woodland

Question 2

What is AR4 and AR5 ?

Answer 2

Fourth Assessment Report and Fifth assessment report which covers over 830 review editors and authors to find evidence for climate change.

Question 3

Indicators for global climate change

Answer 3

Since 1840:
Land surface air, sea surface, and marine air temps are increasing and summer arctic sea ice is lessening

From 1940
Tropospheric temp, ocean heat content, specific humidity, snow cover

Question 4

Whats changing ?

Answer 4

The temperatures are increasing and sea ice extent is reducing, ocean is acidifying

Question 5

Biogeographic effects of climate change

Answer 5

Climate changes the species range of species (maybe due to physiological tolerance)
Ex. zooplankton is related to sea temp - higher temp = more species

Question 6

Changes of species/communities due to climate change

Answer 6

1) Extinction
2) Emigration
3) Evolution

Question 7

Three types of distributional shifts (emigration)

Answer 7

Range retraction, range expansion, range shift

Question 8

Range retraction

Answer 8

range retracts toward center at one or both boundaries without expansion at the other boundary (resulting in extinction)

Question 9

Range expansion

Answer 9

Range expands at one or both boundaries without retraction at the other boundary

Question 10

Range shift

Answer 10

entire range shifts with retraction at one boundary and expansion at the opposite boundary

Question 11

Ex of distributional change

Answer 11

Benthic invertebrates in Monterey Bay in 1930s and 1990s - the north retracted and the south expanded.

Non-migratory butterflies in Europe have shifted north (some southern populations went extinct)

Potential spread of malaria due to global warming

Question 12

Some species/communities lag behind change in climate

Answer 12

Range shifts occur but do not keep pace with the climate change. For example the bat ranges from Forero-Medina

Question 13

Ecoclimatic Index

Answer 13

A measure of the overall climatic favourability of a location for permanent establishment by a taxon based on development and distributional responses to temperature, moisture, and day length. I.e a measure that predicts the extent to which a location has the potential to support a taxon.

Question 14

Climate envelope example

Answer 14

Climate envelope model suggest that some environments in BC will disappear rapidly (like the Sub-boreal pine and spruce, sub-boreal spruce and spruce-willow-birch

Question 15

Climate change scenario

Answer 15

Increase in 3oC in the next century, temperature decreases 6oC per 1000 m elevation.

If species track the change then shift of 500 m elevation

Question 16

Predicting range shifts example

Answer 16

Montane species:
Individuals will move up to the very top of the mountain
Compared to a distribution along the mountain
Modelled by the Resplendent Quetzal

But when considering distance to continental divide the individuals will move closer to the continental divide

Question 17

Cloud forest indicators

Answer 17

Moisture is determined by distance from continental divide - so species composition in a site is better predicted by dist from continental divide than by elevation

Question 18

How to predict species losses?

Answer 18

Use the species-area relationship. In the Great Basin as climate warms the elevation of the boreal forest will increase and the area of each mountain island will decrease. Predict that the number of small mammals on the islands will decrease with this scenario

Question 19

Predicting changes in distributions- Physiology of tropical animals

Answer 19

Tropical species living in stable aseasonal climages have:

• Narrower thermal tolerances than higher latitude species
• Live in climates closer to the physiological optimal
• also ectotherms functions are much more closely related to temperature (ex reproduction, growth etc)
  ex. the amazonian lizard has a narrower range than the temperate lizard

Tropical insects stay close to lethal margin, whereas temperate insects are far away from margin

Question 20

Climate affects who most?

Answer 20

Tropical species

Question 21

Predicting changes biotic processes

Answer 21

Biotic interactions make predictions difficult
Ex. when using three species of drosphila temperature affected the species differently when they were alone compared to together. Ex. melanogaster thrived in high temps where the others were greatly reduced but was not as high alone.

Without dispersal populations went extinct at high temp. Dispersal maintains sink populations

With the thrushes lower level species will be aided by climate change to invade higher species.

Question 22

Predicting changes- challenges

Answer 22

• Lack of knowledge of explicit spatial distributions of species (wallacean shortfall)
• Lack of knowledge of attributes of species and their interactions (hutchinsonian shortfall)
• Shortcomins in the discovery and descriptions of new plant species.