modelling future climate

Question 1

variables and scenarios that affect future emissions

Answer 1

• global economy
• human lifestyle
• political climate

Question 2

CMIP6

Answer 2

• coupled model intercomparison models
• used in AR6 report, the latest IPCC report
• multiple runs of >100 models and 49 modelling groups
• allowed the comparison and calibration of a range of different climate models under different emission scenarios

Question 3

RCP and SSP coupled scenarios

Answer 3

• socioeconomic outcomes affect RCPs
• some coupled scenarios highly unlikely

Question 4

SSP1 = sustainability

Answer 4

• Gradual and continuous move to sustainability
• Rapid move to renewables
• Equitable distribution of wealth
• Curb on population growth
• Stable cooperative governance
• Consumption directed to lower material growth and lower resource/energy intensity

Question 5

SSP2 = middle of the road

Answer 5

• Social, technological and economic trends don’t change notably
• Development of income growth inequitable but patchy
• International cooperation but slow progress
• Still environmental degradation
• Some improvements and a decline in energy intensity
• Income inequalities only slowly improve

Question 6

SSP3 = regional rivalry

Answer 6

• Resurgence of nationalism
• Regional conflict
• Policy shift to national and regional interests
• Regions concentrate on on food security, no wider concern for mitigation
• Investments in education and technology decline
• Consumption is materially orientated and energy intensive
• Population growth, slowly in developed countries and quickly in developing countries

Question 7

SSP4 =inequality

Answer 7

• Large difference in investment in human capital
• Widening differences in economic and political opportunity
• Fragmentation of society between educated knowledge driven and labour intensive low paid work
• Diversification of energy sector to include carbon and renewables
• Environmental issues focused on localised issues in middle and high income areas

Question 8

SSP5 = fossil-fueled development

Answer 8

• Rapid development of technology
• Fueled by fossil fuels
• Strong investment in healthcare and education
• Resource and energy intensive economy
• Global population peaks and declines
• Faith in ability to manage ecological and social systems

Question 9

representative concentration pathways (RCPs)

Answer 9

• represent radiative forcing (w/m²) by the end of the century
• based on future emission scenario predictions taking into account population, land use, energy intensity, energy use

Question 10

problems with predicting climate change

Answer 10

• depends on future emissions
• can’t rely on past records as it is much more rapid than past climate warming

Question 11

improvements in climate models

Answer 11

• better knowledge of systems
• increased computational power

Question 12

most recent IPCC models

Answer 12

• 50-100 layers in ocean and atmosphere
• horizontal resolution of 50-200km²
• updateable every 30 minutes
• contains regional models with much higher resolution

Question 13

radiative forcing, global energy balance

Answer 13

• the changing of energy stores within a system
• solar energy is received (incidence), reflected, stored or used then reemitted
• global temperature depends on the amount of this energy that is emitted into space
• cooling + incidence < emitted
• warming = incidence > emitted

Question 14

global climate models (GCMs)

Answer 14

• comprehensive 3D models based on physical laws represented by mathematical equations
• uses a 3D grid across the globe
• used to model future climate change
• uses sub-models of all major parts of the climate system: ocean, atmosphere, topography, biosphere, cryosphere

Question 15

parameterisation

Answer 15

• some factors happen over a smaller scale than the grids used in CGMs such as atmospheric chemistry, production and movement of aerosols, cloud formation and ocean convection
• smaller scale models within a grid check for accuracy and then an average is taken

Question 16

GCMs in the 1960s, two box model

Answer 16

• tracks a variable in a set geographic zone
• start of simple computational models
• describes the flux of energy between two geographic zones e.g. the tropics and the poles
• equations determine the energy entering and leaving the system and the transfer of energy

Question 17

general circulation models (GCMs)

Answer 17

• grid system over earth forms cells in ocean and atmosphere
• factors in exchange of energy and fluid motion between these cells
• often low resolution due to data gathering and computational power limitations

Question 18

atmospheric GCMs

Answer 18

• includes equations for radiation, atmospheric pressure and temperature
• takes into account albedo, convection and hydrology

Question 19

oceanic GCMs

Answer 19

• includes equations for temperature, surface pressure, moisture and winds
• takes into account conservation of heat, mass, linear movement and salinity

Question 20

AOGCMs

Answer 20

• atmospheric oceanic GCMs
• combines atmosphere and ocean GCMs into a singular model

Question 21

SSPs 1-5

Answer 21

SSP1 = sustainability
SSP2 = middle of the road
SSP3 = regional rivalry
SSP4 = inequality
SSp5 = fossil-fueled development