Climate Change

Question 1

Greenhouse gases

Answer 1

• water vapour
• Carbon dioxide
• Methane
• Nitrous Oxide
• Ozone
• CFCs

Question 2

Greenhouse effect

Answer 2

• Some infrared radiation passes through the atmosphere but most is absorbed and re-emitted in all directions by greenhouse gas molecules and clouds; the effect warms Earth’s surface

Question 3

How does climate change affect living organisms?

Answer 3

• Phenological changes
• Range shifts
• Extinction

Question 4

Phenological changes

Answer 4

• Have to do with timing of certain events in natures (when certain birds migrate, certain flowers bloom etc…)
• Some recorded:
  • Flowering of Japanese cherry trees; happening earlier
  • Emergence of butterflies, happening earlier
  • Mountain pine beetles reproducing twice a year instead of once
  • Arctic ground squirrel emerge from hibernation significantly earlier in males compared to females
• This will have serious implications on ecosystems

Question 5

Phenotypic shifts

Answer 5

• Winter moth has greatest fitness when lay eggs so that their timed to hatch when oak bud bursts and the great tit match their birth dates when winter moth are around to eat
  • But as temperature warms, winter moth peaks happen earlier, the oak bud bursts are earlier but not AS early (so out of sync) and the biggest problem is for the birds; some of the tits have adjusted, but many have not; so can’t rely on food source that they have been relying on
• Spruce bud worm and wood warbler; beginning of reproductive cycle used to be in sync with peaks in the worm, but migration dates have moved up for some of these species BUT not for the wood warbler; but spruce bud worm peaks are earlier, so the bird misses the peak since it isn’t migrating earlier

Question 6

Range Shifts

Answer 6

• Certain population is usually found within a range, and then that range shifts in one direction or another; overall species are moving to the poles
• Southerly birds in the UK whose northern ranges have moved north do better
• Study: 35 different species of migratory butterflies; 63% of those butterflies have ranges that have shifted northward by a significant distance

Question 7

Extinctions

Answer 7

• Harlequin frogs & Golden toads
  • 1980-1996: 73-110 species extinct
  • Due to fungal infections
  • Fungus favoured by increasing temperatures

Question 8

Predicted Extinctions

Answer 8

• 15-37% of plants and animals extinct by 2050
• ~20-30% of species assessed extinct with an increase of 1.5-2 C (~2070)
• ~40-70% with an increase of 3.5C (~2100)

Question 9

How can we mitigate climate change?

Answer 9

• Reduce emissions; minimize our carbon footprint
• Maintain forests; deforestation & forest degradation accounts for about 17% of greenhouse gas emissions every year; forests store carbon
• Stop eating so much red meat; cattle emit methane, a powerful greenhouse gas