Chapter 8: projection of the future climate

Question 1

wx prediction

Answer 1

• initial value problem
• depend on initial conditions

Question 2

climate prediction

Answer 2

trying to tell the evolution of the climate (change & development)

• depend on:
  
  • initial conditions
  • boundary conditions

IV and BV problems

Question 3

climate projection

Answer 3

conditional prediction depends on:

• emission scenarios (concentrations of future GHG’s)

Question 4

the prediction and projection depending on time

Answer 4

• day 3 (weather forecast)
  
  • initial condition problem
• months (seasonal outlooks)
• centuries (climate projections)
  
  • boundary condition problem

Question 5

difference between Initial conditions and boundary conditions

Answer 5

• Initial conditions: can change over the model period
• Boundary conditions: fixed by the models
  
  • example:
    
    • intensity of solar radiation
    • topography
    • atmospheric composition
    • etc..

Question 6

prediction

Answer 6

refers to the short term evolution of the climate system from an initial state under constant boundary conditions

Question 7

projection

Answer 7

how the statistics of the climate system will change in response to the changing boundary conditions

Question 8

the earth is becoming

Answer 8

• hotter
• flatter
• more crowded

Question 9

explain hotter earth

Answer 9

• due to global warming under enhanced GHGs
  
  • mainly due to burning of fossil fuels
• • since 1880 the temperature rise at an average rate of 0.07 c/decade
• over this 137 years (0.1 c/decade) land has warmed faster than oceans (0.06 c/decade)
  
  • since 1970 the global temperature rose at a higher rate (0.17 c/decade)

Question 10

explain flatter earth

Answer 10

• due to technological development
• a combination of technological, market and geopolitical events had leveled (flattened) the global economic platform
  
  • more people from more places take part in global economy (unobstructed global market place)
  • created a huge demand for things
    
    • consume lots of
      
      • energy
      • natural resources
      • land and water
      • emit lots of climate changing GHG’s

Question 11

explain more crowded

Answer 11

• the current growth rate of world population is 1.09% (2018)
• growth rate is slightly decreasing from (1.12% in 2017)
• the annual growth rate reach its peak in the late 1960’s (2%)
• directly proportional to global warming

Question 12

emission senarios meaning

Answer 12

plaussible description of future emission of GHG

Question 13

climate projection depends on

Answer 13

future emissions of GHG

• socio economic changes
• technology changes
• energy and land use

Question 14

climate projection scenarios

Answer 14

• before 2014
  
  • A1B1
  • A2
  • B1
  • B2
• since 2014
  
  • RCP 2.6
    
    • low GHG concentration (radiative forcing)
  • RCP 4.5
  • RCP 6
  • RCP 8.5
    
    • high GHG concentration

Question 15

RCP means

Answer 15

representative concentration pathways

Question 16

RCP’s different from each other in

Answer 16

the assumption on the rate of change of GHG concentration

Question 17

method of finding climate projection

Answer 17

• Boundary conditions (emission scenarios)
  
  • model 1
    
    • climate projection

Question 18

projections based on the RCP’s

Answer 18

the least change is 0.3 c

and the most change is 4.8 c

Question 19

peak in RCPs

Answer 19

• RCP 2.6: 2020
• RCP 4.5: 2040
• RCP 6: 2080
• RCP 8.5: 2100

Question 20

uncertainty in climate projections

Answer 20

• emissions (gasses )
  
  • GHG concentration
    
    • RF (we dont know the exact RF) (depend on feedbacks)
      
      • climate sensitivity