lecture 7

Question 1

why do seasons occur

Answer 1

• Tilt of earth’s axis drives changes in seasons in N and S hemispheres
  At the tropics, seasonal variation in temp and day length are slight

Question 2

describe seasons in northern latitudes

Answer 2

• ○ Red dots = temp = avg changes seasonally - there is a pattern
  ○ Blue dots = precip= more even across the year
  ○ Great similarity in this biome across the globe - convergence of vegetative forms

Question 3

describe seasons in equatorial tropical rain forests

Answer 3

• Temp nvr blw 0, mean temp over years is 26
  
  • Precip is high = more extreme dry and wet seasons

Question 4

what is vegetation like in the mediterranean and why?

Answer 4

• In Mediterranean= relatively similar vegetation - water helps maintain a stable temp
  ○ Patchiness = continental effect
  ○ Vegetation looks similar but diff spp. = convergence due to similar environmental conditions

Question 5

what is the IPCC

Answer 5

• Intergovernmental panel on climate change (IPCC)
  
  • Leading international body for climate change assessment
  • Est. by UN environment program and world meterological organization in 1988

Question 6

what mandate does the IPCC work on? what does it do?

Answer 6

• Mandate - provide the world with a clear scientific view on the current state of knowledge in climate change and its potential environmental and socio-economic impacts
  
  • Reviews and assess recent scientific, technical, and socioeconomic info produced world wide relevant to the understanding of climate change

Question 7

what does the IPCC not do?

Answer 7

• Does NOT conduct any research nor does it monitor climate related data or parameters
  
  • Issues that are global = hard to reach a consensus
  • Synthesize + process data
  • Dynamic process, lots goes on behind the scenes

Question 8

what are the major patterns of climate change?

Answer 8

• Co2 increasing over time, collected via direct sampling of the air
  ○ Compared to years ago- nothing has historically
  ○ Annual zigzag pattern - earth “breathing” - periods of high photosynthesis
  ○ Heatmap shows measurements made across the globe

Question 9

observed changes in annual precip?

Answer 9

• 100 mm per year is very substantial
  
  • Used climactic weather stations to measure it

Question 10

what pattern is seen with sea ice?

Answer 10

• Sea ice melting - shows the impact of small changes in degrees
  
  • Geopolitical issues - trying to establish sovern. For ocean - changes in conservation tactics and issues - more tankers + ships - changes dynamics for organisms
  • Water holds lots of energy without changing temp too much - serves as a buffer
    Heat in water is going up = more hurricanes bc more energy

Question 11

ipcc predictions?

Answer 11

○ Even in the most optimistic - temps go up
○ Measure temp regularly w a satalite and model how air flows, then add and make different assumptions for the model
○ Basis of the model is real world measurements = how much you put in is what you get out
○ Rcp values =different scenarios regarding greenhouse gases

	○ Rcp 2.6 (green) = ideal situation, reduction of carbon emission in co3 over decades 
	○ Rcp 8.5 =  projection if we change nothing 
*

Question 12

what issue arises with sea ice melting?

Answer 12

○ Sea ice extent - high reflectivity loss bc loss of ice/snow = more heating observed

Question 13

how is climate change distributed?

Answer 13

○ Avg change in temp (3 degrees) is not distributed evenly = disproportionate in the north
○ Precip up 40% in the worst case, up 20% in best
○ Splices of biomes having different changes un habitat

Question 14

how accurate are climate models

Answer 14

• Models are tested by going retrospectively and running the model from the past until now - see if its accurate in its prediction
  
  • Less certain the further into the future you go
  • ○ Pattern consistent in the past century
    ○ Partially depends on infrastructure = more ghg