Global warming in the pipeline
Abstrak
Improved knowledge of glacial-to-interglacial global temperature change yields Charney (fast-feedback) equilibrium climate sensitivity 1.2 ± 0.3°C (2σ) per W/m2, which is 4.8°C ± 1.2°C for doubled CO2. Consistent analysis of temperature over the full Cenozoic era—including ‘slow’ feedbacks by ice sheets and trace gases—supports this sensitivity and implies that CO2 was 300–350 ppm in the Pliocene and about 450 ppm at transition to a nearly ice-free planet, exposing unrealistic lethargy of ice sheet models. Equilibrium global warming for today’s GHG amount is 10°C, which is reduced to 8°C by today’s human-made aerosols. Equilibrium warming is not ‘committed’ warming; rapid phaseout of GHG emissions would prevent most equilibrium warming from occurring. However, decline of aerosol emissions since 2010 should increase the 1970–2010 global warming rate of 0.18°C per decade to a post-2010 rate of at least 0.27°C per decade. Thus, under the present geopolitical approach to GHG emissions, global warming will exceed 1.5°C in the 2020s and 2°C before 2050. Impacts on people and nature will accelerate as global warming increases hydrologic (weather) extremes. The enormity of consequences demands a return to Holocene-level global temperature. Required actions include: (1) a global increasing price on GHG emissions accompanied by development of abundant, affordable, dispatchable clean energy, (2) East-West cooperation in a way that accommodates developing world needs, and (3) intervention with Earth’s radiation imbalance to phase down today’s massive human-made ‘geo-transformation’ of Earth’s climate. Current political crises present an opportunity for reset, especially if young people can grasp their situation.
Topik & Kata Kunci
Penulis (57)
J. Hansen
M. Sato
L. Simons
L. Nazarenko
Isabelle Sangha
K. Schuckmann
N. Loeb
M. Osman
Q. Jin
P. Kharecha
G. Tselioudis
E. Jeong
A. Lacis
R. Ruedy
G. Russell
Junji Cao
Jing Li Climate Science
Awareness
Solutions
Columbia Univ. Earth Institute
New York.
Ny
Usa
The Netherlands
s-Hertogenbosch
The Netherlands
Nasa Goddard Institute for Space Studies
Center for Space Research
Mercator Ocean International
Ramonville St.-Agne
France
Nasa Langley Research Center
Hampton
Va
Department of Geosciences
U. Arizona
Tucson
Az
Department of Geography
Atmospheric Science
U. Kansas
Lawrence
Ks
Csas Korea
Goyang
Gyeonggi-do
S. Korea
Business Integra
Inc.
Institute of Physics
Chinese Academy of Sciences
Beijing
China.
Department of Atmospheric
Oceanic Sciences
S. O. Physics
P. University
Akses Cepat
- Tahun Terbit
- 2022
- Bahasa
- en
- Total Sitasi
- 229×
- Sumber Database
- Semantic Scholar
- DOI
- 10.1093/oxfclm/kgad008
- Akses
- Open Access ✓