Global Warming Forecast using Acceleration Factors

Abstract

This publication introduces four methods to forecast the global surface temperature over land and ocean (global warming). The methods include a parabolic trendline of the last 61 years of global warming and cumulated CO2 emissions. Two other methods apply the velocity and the acceleration of global warming and cumulative CO2 emissions. The relation between the global surface temperature change and the change in the cumulative CO2 emissions was determined in previous publications as 0.000745°C/GtCO2. The average result from all four methods for the business as usual CO2 mitigation scenario is 4.4°C (4.1°C-5.0°C). According to this forecast, the global temperature change will reach 1.5°C in 2031 (9 years from now) and 2.0°C in 2047 (25 years from now).

Full text

Global Warming Forecast using Acceleration Factors
Joseph Nowarski, M.Sc., ME – Energy Conservation Expert
Version 1.1.1, 6 June 2022
DOI:10.5281/zenodo.6621042
all versions DOI:10.5281/zenodo.6621041
Keywords: Climate Change
Global Warming
cumulative CO2
Global Warming forecast
global temperature forecast
CO2 mitigation
Abstract
This publication introduces four methods to forecast the global surface
temperature over land and ocean (global warming).
The methods include a parabolic trendline of the last 61 years of global warming
and cumulated CO2 emissions.
Two other methods apply the velocity and the acceleration of global warming
and cumulative CO2 emissions.
The relation between the global surface temperature change and the change in
the cumulative CO2 emissions was determined in previous publications as
0.000745°C/GtCO2.
The average result from all four methods for the business as usual CO2 mitigation
scenario is 4.4°C (4.1°C -5.0°C).
According to this forecast, the global temperature change will reach 1.5°C in 2031
(9 years from now) and 2.0°C in 2047 (25 years from now).

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Glossary
ACCO2 acceleration of change in cumulative CO2 emissions, tCO2/y2 (ton
CO2 per year per year)
Ave average
BL baseline of surface temperature change (GW) 1850-1900
CCO2 global cumulative CO2 emissions according to publication [10] [11],
CO2 emissions produced from fossil fuels and cement production only
– land use change is not included
CO2 emissions of Carbon Dioxide, CO2
dCO2 change in global cumulative CO2 emissions (CCO2), tCO2/y (ton CO2
per year)
GtCO2 Giga-ton of CO2, 109 ton, 10^9 ton, 1,000,000,000 ton of CO2
GW Global Warming, global surface temperature above the 1850-1900
baseline, land+ocean, °C
GWA Global Warming Acceleration, annual change in the Global Warming
Rate, °C/y2 [2]
GWR Global Warming Rate – average change in global surface
temperature per year in the trendline period, °C/y [2]
OWID Our World in Data – Internet site [10] [11]
Ref reference
tCO2 ton CO2
TL trendline
VCCO2 velocity of change in cumulative CO2 emissions, tCO2/y

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Business As Usual Scenario
All calculations and estimations in this work are for the Business As Usual (BAU)
scenario, the effectiveness of the future CO2 emissions mitigation will be as in the
past.
Part I – Forecast of Global Surface Temperature Change based on Global
Warming Rate and Global Warming Acceleration
Global Surface Temperature Changes
The dataset of global surface temperature changes for land and ocean
converted to 1850-1900 baseline is publicly available on
DOI:10.5281/zenodo.6386191 [1]. The dataset is based on NASA [5] [6], NOAA [7],
and Berkley Earth [8] [9].
Chart 1 - Trendlines, land+ocean, 1850-1900 baseline [°C] [1]
-0.5
-0.3
-0.1
0.1
0.3
0.5
0.7
0.9
1.1
1.3
1.5
1850
1860
1870
1880
1890
1900
1910
1920
1930
1940
1950
1960
1970
1980
1990
2000
2010
2020
Ave TL1 TL2 TL3 TL4
Ave average of all databases [°C]

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Chart 2 - GW parabolic trendline 1961-2021 [°C]
y = 0.000128286617 x2 + 0.009482577384 x + 0.223886718533
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
1961
1971
1981
1991
2001
2011
2021
2031
2041
2051
2061
2071
2081
2091
According to the most recent 61 years parabolic trendline, the GW forecast for the
year 2100 is 4.07°C above the 1850-1900 baseline.
Global Warming Rate and Global Warming Acceleration
All details about Global Warming Rate (GWR) and Global Warming Acceleration
(GWA) are from the publication “Global Warming Acceleration“ [2].
In publication [2], the Global Warming Rate (GWR) was defined as “average
change in global surface temperature per year in the trendline period, °C/y”, and
Global Warming Acceleration (GWA) as “annual change in the global warming
rate, °C/y2”.
Chart 3 - GWR – Global Warming Rate, land+ocean [°C/y] [2]
-0.005
0.000
0.005
0.010
0.015
0.020
1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1991
Axis x is the center of the 61 years trendline period

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Chart 4 - GWA - Global Warming Acceleration, land+ocean [°C/y2] [2]
TL(GWA) = 0.000032352964 x - 0.000041422880
-0.0002
-0.0001
0.0000
0.0001
0.0002
0.0003
0.0004
0.0005
0.0006
1920
1930
1940
1950
1960
1970
1980
1990
2000
2010
2020
Axis x is the end of the 61 years trendline period
Since 1980 the GWA is above zero, which means the Global Warming Rate (GWR)
[°C/y] is increasing. The negative slope of GWA between 1980 and 1991 means a
slower increase in GWR.
Currently, the Global Warming Acceleration (GWA) is decreasing by
0.0000174°C/y2 per year (°C/y3), however, over the maximum period, the GWA is
increasing according to the trendline formula displayed on the above chart.
The forecast for the next decade may be based on the last dGWA, but for the
longer period, the maximum period trendline formula is more appropriate.
Therefore the forecast of the acceleration change till the end of the 21st century is
based on the maximum period linear trendline formula, which results in
+0.000003235°C/y3.
Table 1 - Initial values for forecast [2]
Starting TL TL GW(BL)
GWR GWA dGWA
year a b TL
°C °C/y °C/y2 °C/y3
2020
+0.017213 +0.132767 +1.183 +0.017213414 +0.000385144 +0.000003235

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Table 2 - GW forecast using GW acceleration approach
year dGWA GWA GWR GW(BL) year dGWA GWA GWR GW(BL)
°C/y3 °C/y2 °C/y °C °C/y3 °C/y2 °C/y °C
2020 +0.0000032 +0.0003851
+0.0172134
1.183
2061
+0.0000032
+0.0005178
+0.0357899 2.260
2021 +0.0000032 +0.0003884 +0.0176
018
1.200
2062
+0.0000032
+0.0005210
+0.0363109 2.296
2022 +0.0000032 +0.0003916
+0.0179934
1.218
2063
+0.0000032
+0.0005243
+0.0368352 2.333
2023 +0.0000032 +0.0003948
+0.0183883
1.237
2064
+0.0000032
+0.0005275
+0.0373627 2.371
2024 +0.0000032 +0.0003981
+0.0187863
1.256
2065
+0.0000032
+0.0005307
+0.0378934 2.408
2025 +0.0000032 +0.0004013
+0.0191877
1.275
2066
+0.0000032
+0.0005340
+0.0384274 2.447
2026 +0.0000032 +0.0004046
+0.0195922
1.294
2067
+0.0000032
+0.0005372
+0.0389646 2.486
2027 +0.0000032 +0.0004078
+0.0200000
1.314
2068
+0.0000032
+0.0005404
+0.0395050 2.525
2028 +0.0000032 +0.0004110
+0.0204110
1.335
2069
+0.0000032
+0.0005437
+0.0400487 2.565
2029 +0.0000032 +0.0004143
+0.0208253
1.356
2070
+0.0000032
+0.0005469
+0.0405956 2.606
2030 +0.0000032 +0.0004175
+0.0212428
1.377
2071
+0.0000032
+0.0005501
+0.0411457 2.647
2031 +0.0000032 +0.0004207
+0.0216635
1.398
2072
+0.0000032
+0.0005534
+0.0416991 2.689
2032 +0.0000032 +0.0004240
+0.0220875
1.421
2073
+0.0000032 +0.0005
566
+0.0422557 2.731
2033 +0.0000032 +0.0004272
+0.0225147
1.443
2074
+0.0000032
+0.0005598
+0.0428156 2.774
2034 +0.0000032 +0.0004304
+0.0229451
1.466
2075
+0.0000032
+0.0005631
+0.0433787 2.817
2035 +0.0000032 +0.0004337
+0.0233788
1.489
2076
+0.0000032
+0.0005663
+0.0439450 2.861
2036 +0.0000032 +0.0004369
+0.0238157
1.513
2077
+0.0000032
+0.0005696
+0.0445145 2.906
2037 +0.0000032 +0.0004401
+0.0242559
1.537
2078
+0.0000032
+0.0005728
+0.0450873 2.951
2038 +0.0000032 +0.0004434
+0.0246992
1.562
2079
+0.0000032
+0.0005760
+0.0456634 2.997
2039 +0.0000032 +0.0004466
+0.0251459
1.587
2080
+0.0000032
+0.0005793
+0.0462426 3.043
2040 +0.0000032 +0.0004498
+0.0255957
1.613
2081
+0.0000032
+0.0005825
+0.0468251 3.090
2041 +0.0000032 +0.0004531
+0.0260488
1.639
2082
+0.0000032
+0.0005857
+0.0474109 3.137
2042 +0.0000032 +0.0004563
+0.0265051
1.665
2083
+0.0000032
+0.0005890
+0.0479998 3.185
2043 +0.0000032 +0.0004596
+0.0269647
1.692
2084
+0.0000032
+0.0005922
+0.0485920 3.234
2044 +0.0000032 +0.0004628
+0.0274275
1.720
2085
+0.0000032
+0.0005954
+0.0491875 3.283
2045 +0.0000032 +0.0004660
+0.0278935
1.748
2086
+0.0000032
+0.0005987
+0.0497861 3.333
2046 +0.0000032 +0.0004693
+0.0283627
1.776
2087
+0.0000032
+0.0006019
+0.0503880 3.383
2047 +0.0000032 +0.0004725
+0.0288352
1.805
2088
+0.0000032
+0.0006051
+0.0509932 3.434
2048 +0.0000032 +0.0004757
+0.0293110
1.834
2089
+0.0000032
+0.0006084
+0.0516016 3.486
2049 +0.0000032 +0.0004790
+0.0297899
1.864
2090
+0.0000032
+0.0006116
+0.0522132 3.538
2050 +0.0000032 +0.0004822
+0.0302721
1.894
2091
+0.0000032
+0.0006148
+0.0528280 3.591
2051 +0.0000032 +0.0004854
+0.0307576
1.925
2092
+0.0000032
+0.0006181
+0.0534461 3.644
2052 +0.0000032 +0.0004887
+0.0312462
1.956
2093
+0.0000032
+0.0006213
+0.0540674 3.698
2053 +0.0000032 +0.0004919
+0.0317382
1.988
2094
+0.0000032
+0.0006246
+0.0546920 3.753
2054 +0.0000032 +0.0004951
+0.0322333
2.020
2095
+0.0000032
+0.0006278
+0.0553198 3.808
2055 +0.0000032 +0.0004984
+0.0327317
2.053
2096
+0.0000032
+0.0006310
+0.0559508 3.864
2056 +0.0000032 +0.0005016
+0.0332333
2.086
2097
+0.0000032
+0.0006343
+0.0565851 3.921
2057 +0.0000032 +0.0005048
+0.0337381
2.120
2098
+0.0000032
+0.0006375
+0.0572226 3.978
2058 +0.0000032 +0.0005081 +0.03
42462
2.154
2099
+0.0000032
+0.0006407
+0.0578633 4.036
2059 +0.0000032 +0.0005113
+0.0347575
2.189
2100
+0.0000032
+0.0006440
+0.0585073 4.094
2060 +0.0000032 +0.0005146
+0.0352721
2.224
Part II – Forecast of Global Surface Temperature Change based on Cumulative
CO2 Emissions
The annual changes in cumulative CO2 emissions were calculated in publication
“Global Warming: Velocity and Acceleration of Change in Cumulative CO2
Emissions” [3] based on publications [10] [11].

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Table 3 - Database of global cumulative CO2 emissions [10] [11]
Source of Data OWID
Reference [10] [11]
Baseline year 1749
From year 1750
To year 2020
Period, years 271
CO2 from fossil fuels Yes
CO2 from cement production Yes
CO2 from other sources No
Other GHG No
Land use change No
Units ton CO2
Resolution 1 ton CO2/y
The database is from publication [10] [11], CO2 emissions produced from fossil fuels
and cement production only – land use change is not included.
Chart 5 - Annual change in the cumulated CO2 emissions [GtCO2/y]
[3]
0
5
10
15
20
25
30
35
40
1750
1770
1790
1810
1830
1850
1870
1890
1910
1930
1950
1970
1990
2010

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Chart 6 - CCO2 parabolic trendline 1960-2020 [GtCO2] [3]
y = 0.216508612383 x2 + 9.560926272347 x + 297.027530655321
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
1960
1970
1980
1990
2000
2010
2020
2030
2040
2050
2060
2070
2080
2090
2100
According to the most recent 61 years parabolic trendline, the CCO2 forecast for
the year 2100 is 5,949.53GtCO2.
Correlation between Cumulative CO2 Emissions and Global Temperature
The correlation between the cumulative CO2 emissions and Global Warming,
CO2GW, was analyzed in publication [4].
Formula 1 - CO2 to global warming, CO2GW, average GW in two
31 years periods, and CCO2 in the center of the periods
[4]
CO2GW= dGW / dCCO2
CO2GW relation between global cumulative CO2 emissions according
to publication [10] [11], CCO2, and the change in global
surface temperature, GW, °C/GtCO2
dGW change in average GW between two 31 years periods, °C
dCCO2 change in CCO2 between the centers of two periods, GtCO2
Two most recent 31 neighboring periods were selected in this work for the
determination of CO2GW: 1961-1991 and 1991-2021.

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Table 4 - Application of Formula 1 for the year 2000
1940-1970 1970-2000 Δ
Center year 1955 1985
Ave GW °C +0.307 +0.548 +0.241
CCO2 GtCO2 264.04 698.46 434.42
CO2GW °C/GtCO2 0.000556
Table 5 - Application of Formula 1 for the year 2021
1961-1991 1991-2021 Δ
Center year 1976 2006
Ave GW °C +0.425 +0.938 +0.513
CCO2 GtCO2 524.92 1,212.72 687.80
CO2GW °C/GtCO2 0.000745
CO2GW = 0.000745°C/GtCO2
Table 6 - Velocity of change in CO2GW, VCO2GW [°C/(GtCO2,y)]
Δ
Center of Period year 1985 2006
21
CO2GW °C/GtCO2 0.000556 0.000745
+0.000190
VCO2GW °C/(GtCO2,y) +0.000009
Forecast of Global Warming in 2100 using Parabolic Trendline of Cumulative CO2
Emissions
Table 7 - Forecast of Global Warming in 2100 using parabolic trendline of
cumulative CO2 emissions [°C]
1875 2100
BL from 1850
BL to 1900
BL Center 1875
CCO2 GtCO2 14.92 5,949.53
ΔCCO2 GtCO2 5,934.61
CO2GW °C/GtCO2 0.00074544
ΔGW °C 4.424
GW °C 0 4.424
According to the above approach, the GW forecast for the year 2100 is 4.42°C
above the 1850-1900 baseline.

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Velocity and Acceleration of Cumulative CO2 Emissions
All details about the Velocity (VCCO2) and Acceleration (ACCO2) of Cumulative
CO2 Emissions are from the publication “Velocity and Acceleration of Cumulative
CO2 Emissions“ [3].
In publication [3], the Velocity of Change in Cumulative CO2 Emissions (VCCO2)
was defined as “11 years average of annual changes in cumulative CO2
emissions, tCO2/y” and the Acceleration of Change in Cumulative CO2 Emissions
(ACCO2) as “31 years trendline slope of the annual changes in the cumulative
CO2 emissions, tCO2/ y2”.
Chart 7 - Velocity of Change in Cumulative CO2 Emissions, VCCO2
[GtCO2/y] [3]
0
5
10
15
20
25
30
35
40
1755
1765
1775
1785
1795
1805
1815
1825
1835
1845
1855
1865
1875
1885
1895
1905
1915
1925
1935
1945
1955
1965
1975
1985
1995
2005
2015
Axis x is the center of the 11 years period applied for the calculation

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Chart 8 - Acceleration of Change in Cumulative CO2 Emissions, ACCO2
[GtCO2/y2], [Giga-ton CO2 per year per year] [3]
y = 0.020664973607x - 0.139577412972
-0.1
0.0
0.1
0.2
0.3
0.4
0.5
0.6
1765
1775
1785
1795
1805
1815
1825
1835
1845
1855
1865
1875
1885
1895
1905
1915
1925
1935
1945
1955
1965
1975
1985
1995
2005
Axis x is the center of the 31 trendline period (2005 is the center of the 1990-2020 trendline period)
Table 8 - Annual change in Acceleration of Cumulative CO2 Emissions,
dACCO2 [GtCO2/y3]
ACCO2 Linear Trendline Formula y = 0.020664973607x - 0.139577412972
Δy 10 y
TL a
0.020664974
dACCO2 0.002066497 GtCO2/y3
Table 9 - Starting point for the forecast [3]
Trendline Starting CCO2 VCCO2 ACCO2 dACCO2
from to year
GtCO2 GtCO2/y GtCO2/y2 GtCO2/y3
1990
2020
2020 1,697 35.33 +0.5590470 +0.0020665

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Table 10 - GW forecast using CCO2 acceleration approach
year
dACCO2
ACCO2 VCCO2
CCO2
Δ to BL
GW year
dACCO2
ACCO2 VCCO2
CCO2
Δ to BL
GW
GtCO2/y3
GtCO2/y2
GtCO2/y
GtCO2
GtCO2
°C GtCO2/y3
GtCO2/y2
GtCO2/y
GtCO2
GtCO2
°C
2020 +0.002
+0.569 38.16 1,702
1,687 1.258 2061 +0.002
+0.654 63.28 3,782
3,767 2.808
2021 +0.002
+0.571 38.73 1,741
1,726 1.287 2062 +0.002
+0.656 63.94 3,846
3,831 2.856
2022 +0.002
+0.574 39.30 1,780
1,765 1.316 2063 +0.002
+0.658 64.59 3,911
3,896 2.904
2023 +0.002
+0.576 39.88 1,820
1,805 1.346 2064 +0.002
+0.660 65.26 3,976
3,961 2.953
2024 +0.002
+0.578 40.45 1,860
1,846 1.376 2065 +0.002
+0.662 65.92 4,042
4,027 3.002
2025 +0.002
+0.580 41.03 1,901
1,887 1.406 2066 +0.002
+0.664 66.58 4,109
4,094 3.052
2026 +0.002
+0.582 41.62 1,943
1,928 1.437 2067 +0.002
+0.667 67.25 4,176
4,161 3.102
2027 +0.002
+0.584 42.20 1,985
1,970 1.469 2068 +0.002
+0.669 67.92 4,244
4,229 3.152
2028 +0.002
+0.586 42.79 2,028
2,013 1.501 2069 +0.002
+0.671 68.59 4,312
4,297 3.203
2029 +0.002
+0.588 43.37 2,071
2,057 1.533 2070 +0.002
+0.673 69.26 4,382
4,367 3.255
2030 +0.002
+0.590 43.96 2,115
2,101 1.566 2071 +0.002
+0.675 69.94 4,451
4,437 3.307
2031 +0.002
+0.592 44.56 2,160
2,145 1.599 2072 +0.002
+0.677 70.61 4,522
4,507 3.360
2032 +0.002
+0.594 45.15 2,205
2,190 1.633 2073 +0.002
+0.679 71.29 4,593
4,578 3.413
2033 +0.002
+0.596 45.75 2,251
2,236 1.667 2074 +0.002
+0.681 71.97 4,665
4,650 3.467
2034 +0.002
+0.598 46.34 2,297
2,282 1.701 2075 +0.002
+0.683 72.65 4,738
4,723 3.521
2035 +0.002
+0.600 46.95 2,344
2,329 1.736 2076 +0.002
+0.685 73.34 4,811
4,796 3.575
2036 +0.002
+0.602 47.55 2,392
2,377 1.772 2077 +0.002
+0.687 74.03 4,885
4,870 3.631
2037 +0.002
+0.605 48.15 2,440
2,425 1.808 2078 +0.002
+0.689 74.72 4,960
4,945 3.686
2038 +0.002
+0.607 48.76 2,489
2,474 1.844 2079 +0.002
+0.691 75.41 5,036
5,021 3.743
2039 +0.002
+0.609 49.37 2,538
2,523 1.881 2080 +0.002
+0.693 76.10 5,112
5,097 3.799
2040 +0.002
+0.611 49.98 2,588
2,573 1.918 2081 +0.002
+0.695 76.80 5,188
5,173 3.857
2041 +0.002
+0.613 50.59 2,639
2,624 1.956 2082 +0.002
+0.698 77.49 5,266
5,251 3.914
2042 +0.002
+0.615 51.21 2,690
2,675 1.994 2083 +0.002
+0.700 78.19 5,344
5,329 3.973
2043 +0.002
+0.617 51.82 2,742
2,727 2.033 2084 +0.002
+0.702 78.90 5,423
5,408 4.031
2044 +0.002
+0.619 52.44 2,794
2,779 2.072 2085 +0.002
+0.704 79.60 5,503
5,488 4.091
2045 +0.002
+0.621 53.06 2,847
2,832 2.111 2086 +0.002
+0.706 80.30 5,583
5,568 4.151
2046 +0.002
+0.623 53.69 2,901
2,886 2.151 2087 +0.002
+0.708 81.01 5,664
5,649 4.211
2047 +0.002
+0.625 54.31 2,955
2,940 2.192 2088 +0.002
+0.710 81.72 5,746
5,731 4.272
2048 +0.002
+0.627 54.94 3,010
2,995 2.233 2089 +0.002
+0.712 82.43 5,828
5,813 4.333
2049 +0.002
+0.629 55.57 3,066
3,051 2.274 2090 +0.002
+0.714 83.15 5,911
5,896 4.395
2050 +0.002
+0.631 56.20 3,122
3,107 2.316 2091 +0.002
+0.716 83.86 5,995
5,980 4.458
2051 +0.002
+0.633 56.83 3,179
3,164 2.358 2092 +0.002
+0.718 84.58 6,080
6,065 4.521
2052 +0.002
+0.636 57.47 3,236
3,221 2.401 2093 +0.002
+0.720 85.30 6,165
6,150 4.585
2053 +0.002
+0.638 58.11 3,294
3,279 2.445 2094 +0.002
+0.722 86.03 6,251
6,236 4.649
2054 +0.002
+0.640 58.75 3,353
3,338 2.488 2095 +0.002
+0.724 86.75 6,338
6,323 4.713
2055 +0.002
+0.642 59.39 3,412
3,397 2.533 2096 +0.002
+0.726 87.48 6,425
6,410 4.779
2056 +0.002
+0.644 60.03 3,472
3,457 2.577 2097 +0.002
+0.728 88.20 6,513
6,499 4.844
2057 +0.002
+0.646 60.68 3,533
3,518 2.623 2098 +0.002
+0.731 88.94 6,602
6,587 4.911
2058 +0.002
+0.648 61.32 3,594
3,579 2.668 2099 +0.002
+0.733 89.67 6,692
6,677 4.977
2059 +0.002
+0.650 61.97 3,656
3,641 2.714 2100 +0.002
+0.735 90.40 6,782
6,768 5.045
2060 +0.002
+0.652 62.63 3,719
3,704 2.761

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Part III – Forecast of Global Surface Temperature Change till 2100
Forecast Methods
The forecast is done in this work using the following methods:
 Parabolic trendline of Global Warming (GWTL)
 Global Warming acceleration factors (GWA)
 Cumulative CO2 emissions parabolic trendline (CO2TL)
 Cumulative CO2 emissions acceleration factors (CO2A)

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Table 11 - Business as usual (BAU) GW forecast using all methods, °C above
1850-1900 baseline, for land+ocean
year GWTL
GWA CO2TL
CO2A Ave year GWTL GWA CO2TL
CO2A Ave
2020
1.255 1.183 1.246 1.258 1.235
2061
2.490 2.260 2.616 2.808 2.544
2021
1.280 1.200 1.273 1.287 1.260
2062
2.526 2.296 2.657 2.856 2.584
2022
1.305 1.218 1.300 1.316 1.285
2063
2.562 2.333 2.697 2.904 2.624
2023
1.330 1.237 1.328 1.346 1.310
2064
2.598 2.371 2.738 2.953 2.665
2024
1.356 1.256 1.355 1.376 1.336
2065
2.634 2.408 2.779 3.002 2.706
2025
1.382 1.275 1.384 1.406 1.362
2066
2.670 2.447 2.821 3.052 2.747
2026
1.409 1.294 1.412 1.437 1.388
2067
2.707 2.486 2.863 3.102 2.789
2027
1.435 1.314 1.441 1.469 1.415
2068
2.744 2.525 2.905 3.152 2.832
2028
1.462 1.335 1.470 1.501 1.442
2069
2.782 2.565 2.947 3.203 2.874
2029
1.489 1.356 1.500 1.533 1.469
2070
2.819 2.606 2.990 3.255 2.918
2030
1.516 1.377 1.530 1.566 1.497
2071
2.857 2.647 3.033 3.307 2.961
2031
1.544 1.398 1.560 1.599 1.525
2072
2.895 2.689 3.077 3.360 3.005
2032
1.572 1.421 1.591 1.633 1.554
2073
2.934 2.731 3.120 3.413 3.049
2033
1.600 1.443 1.622 1.667 1.583
2074
2.972 2.774 3.164 3.467 3.094
2034
1.628 1.466 1.653 1.701 1.612
2075
3.011 2.817 3.209 3.521 3.139
2035
1.657 1.489 1.684 1.736 1.642
2076
3.050 2.861 3.254 3.575 3.185
2036
1.686 1.513 1.716 1.772 1.672
2077
3.089 2.906 3.299 3.631 3.231
2037
1.715 1.537 1.748 1.808 1.702
2078
3.129 2.951 3.344 3.686 3.278
2038
1.744 1.562 1.781 1.844 1.733
2079
3.169 2.997 3.390 3.743 3.324
2039
1.774 1.587 1.813 1.881 1.764
2080
3.209 3.043 3.436 3.799 3.372
2040
1.804 1.613 1.847 1.918 1.795
2081
3.250 3.090 3.482 3.857 3.419
2041
1.834 1.639 1.880 1.956 1.827
2082
3.290 3.137 3.529 3.914 3.468
2042
1.864 1.665 1.914 1.994 1.859
2083
3.331 3.185 3.576 3.973 3.516
2043
1.895 1.692 1.948 2.033 1.892
2084
3.372 3.234 3.623 4.031 3.565
2044
1.926 1.720 1.982 2.072 1.925
2085
3.414 3.283 3.671 4.091 3.614
2045
1.957 1.748 2.017 2.111 1.958
2086
3.455 3.333 3.719 4.151 3.664
2046
1.988 1.776 2.052 2.151 1.992
2087
3.497 3.383 3.767 4.211 3.715
2047
2.020 1.805 2.087 2.192 2.026
2088
3.540 3.434 3.815 4.272 3.765
2048
2.052 1.834 2.123 2.233 2.060
2089
3.582 3.486 3.864 4.333 3.816
2049
2.084 1.864 2.159 2.274 2.095
2090
3.625 3.538 3.914 4.395 3.868
2050
2.116 1.894 2.195 2.316 2.131
2091
3.668 3.591 3.963 4.458 3.920
2051
2.149 1.925 2.232 2.358 2.166
2092
3.711 3.644 4.013 4.521 3.972
2052
2.182 1.956 2.269 2.401 2.202
2093
3.754 3.698 4.063 4.585 4.025
2053
2.215 1.988 2.306 2.445 2.239
2094
3.798 3.753 4.114 4.649 4.078
2054
2.249 2.020 2.344 2.488 2.275
2095
3.842 3.808 4.165 4.713 4.132
2055
2.283 2.053 2.382 2.533 2.313
2096
3.886 3.864 4.216 4.779 4.186
2056
2.317 2.086 2.420 2.577 2.350
2097
3.931 3.921 4.267 4.844 4.241
2057
2.351 2.120 2.459 2.623 2.388
2098
3.976 3.978 4.319 4.911 4.296
2058
2.385 2.154 2.498 2.668 2.426
2099
4.021 4.036 4.371 4.977 4.351
2059
2.420 2.189 2.537 2.714 2.465
2100
4.066 4.094 4.424 5.045 4.407
2060
2.455 2.224 2.577 2.761 2.504
GWTL Parabolic trendline of Global Warming
GWA Global Warming acceleration factors
CO2TL Cumulative CO2 emissions parabolic trendline
CO2A Cumulative CO2 emissions acceleration factors
Ave Average of all approaches
The estimation of the global surface temperature over land and ocean in 2100 for
the business as usual scenario is 4.4°C above the 1850-1900 baseline

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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Chart 9 - Business as usual (BAU) GW forecast using all methods, °C
above 1850-1900 baseline, for land+ocean
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
2020
2030
2040
2050
2060
2070
2080
2090
2100
GWTL GWA CO2TL CO2A Ave

Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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References
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Baseline v1.1.2 – Joseph Nowarski, DOI:10.5281/zenodo.6461153
2. Global Warming Acceleration v1.2.1 - Joseph Nowarski,
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3. Global Warming: Velocity and Acceleration of Change in Cumulative CO2
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4. Global Warming and Cumulative CO2 – Joseph Nowarski,
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Global Warming Forecast using Acceleration Factors - Joseph Nowarski
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https://ourworldindata.org/grapher/cumulative-co-emissions
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