In 2018, the biggest change in fossil fuel applications (EF) was due to a significant increase in energy demand and CO 2 emissions in China. In this country, the
increases in coal, oil, and natural gas demands for the same year were 4.5, 3.6, and
17.7%, respectively. The increase in natural gas consumption was due to China´s
policy for climate change mitigation.
Global carbon components need to be evaluated to assess the state of the
environment, vulnerable to fast changes in biophysical and anthropogenic factors.
These include variations in growth rates of fossil fuel emissions, environment
temperatures, and dynamics of carbon sinks. Also, time series of data sets are
essential to predict the carbon cycle, and many organizations, such as universities
and laboratories, governments, private companies, and media, rely on these data
sets to respond to climate change mitigation.
8.3 Alternative Scenarios for Climate Change Predictions
The AR4 and AR5 Reports describe sets of alternative GHG emissions scenarios
linked with projections for atmospheric temperature increases. At present, the
average global warming is 0.85 °C relative to the pre-industrial era (Fischer and
Knutti 2015).
Under AR4, six climate change scenarios were proposed: B1, AIT, B2, A1B,
A2, and A1FI, corresponding to atmospheric concentrations hypothesis of GHG
(CO 2 -eq.), in 2100 of 600, 700, 800, 850, 1250, and 1550 ppm, respectively.
The temperature and sea-level changes estimated under these scenarios, comparing the periods 2090–2099 and 1980–1999, are synthesized in Table 8.1.
The ranges reflect the limited understanding of physical mechanisms such as
feedback from the carbon and carbon dioxide cycles (AR4 Report).
The six scenarios from four climate major trend scenarios (A1, A2, B1, and B2)
assume alternative socioeconomic development roadmaps, encompassing a wide
range of GHG emissions and demographic, economic, and technological driving
forces which input into projections of climate change vulnerability. These six
scenarios do not assume additional climate policies, besides the current ones.
The A1 scenario assumes high global economic growth, a global population
peaking in the mid-twenty-first century, and a fast introduction of new efficient
technologies. This scenario is divided into three which are A1FI for fossil intensive
Table 8.1 Characterization of climate change scenarios under the AR4 IPCC report
Climate scenarios
B1
A1T
B2
A1B
A2
A1F1
Temperature
variations, °C
1.8
2.4
2.4
2.8
3.4
4.0
Temperature ranges, °
C
1.1–2.9
1.4–3.8
1.4–3.8
1.7–4.4
2.0–5.4
2.4–6.4
Sea-level rise
projections, m
0.18–
0.38
0.20–
0.45
0.20–
0.43
0.21–
0.48
0.23–
0.51
0.26–
0.59
278
8 Fundamentals of Global Carbon Budgets and Climate Change
increases in coal, oil, and natural gas demands for the same year were 4.5, 3.6, and
17.7%, respectively. The increase in natural gas consumption was due to China´s
policy for climate change mitigation.
Global carbon components need to be evaluated to assess the state of the
environment, vulnerable to fast changes in biophysical and anthropogenic factors.
These include variations in growth rates of fossil fuel emissions, environment
temperatures, and dynamics of carbon sinks. Also, time series of data sets are
essential to predict the carbon cycle, and many organizations, such as universities
and laboratories, governments, private companies, and media, rely on these data
sets to respond to climate change mitigation.
8.3 Alternative Scenarios for Climate Change Predictions
The AR4 and AR5 Reports describe sets of alternative GHG emissions scenarios
linked with projections for atmospheric temperature increases. At present, the
average global warming is 0.85 °C relative to the pre-industrial era (Fischer and
Knutti 2015).
Under AR4, six climate change scenarios were proposed: B1, AIT, B2, A1B,
A2, and A1FI, corresponding to atmospheric concentrations hypothesis of GHG
(CO 2 -eq.), in 2100 of 600, 700, 800, 850, 1250, and 1550 ppm, respectively.
The temperature and sea-level changes estimated under these scenarios, comparing the periods 2090–2099 and 1980–1999, are synthesized in Table 8.1.
The ranges reflect the limited understanding of physical mechanisms such as
feedback from the carbon and carbon dioxide cycles (AR4 Report).
The six scenarios from four climate major trend scenarios (A1, A2, B1, and B2)
assume alternative socioeconomic development roadmaps, encompassing a wide
range of GHG emissions and demographic, economic, and technological driving
forces which input into projections of climate change vulnerability. These six
scenarios do not assume additional climate policies, besides the current ones.
The A1 scenario assumes high global economic growth, a global population
peaking in the mid-twenty-first century, and a fast introduction of new efficient
technologies. This scenario is divided into three which are A1FI for fossil intensive
Table 8.1 Characterization of climate change scenarios under the AR4 IPCC report
Climate scenarios
B1
A1T
B2
A1B
A2
A1F1
Temperature
variations, °C
1.8
2.4
2.4
2.8
3.4
4.0
Temperature ranges, °
C
1.1–2.9
1.4–3.8
1.4–3.8
1.7–4.4
2.0–5.4
2.4–6.4
Sea-level rise
projections, m
0.18–
0.38
0.20–
0.45
0.20–
0.43
0.21–
0.48
0.23–
0.51
0.26–
0.59
278
8 Fundamentals of Global Carbon Budgets and Climate Change