File:ECS assessments IPCC.png

Page contents not supported in other languages.
This is a file from the Wikimedia Commons
From Wikipedia, the free encyclopedia

Original file ‎(1,647 × 1,145 pixels, file size: 62 KB, MIME type: image/png)

Summary

Description
English: Estimates of climate sensitivity by different assessments reports of the IPCC.

The IPCC estimates of the first three reports (FAR, SAR, TAR) did not give a formal definition of uncertainty, whereas the fourth (AR4) and the fifth (AR5) report denoted a 66% likelihood range for values between 2-4.5 degrees and 1.5 degrees respectively.

  • The first IPCC report states that for a doubling of carbon dioxide: "near the Earth's surface, the global average wanning lies between +1.5°C and +4.5°C, with a "best guess" of 2.5°C". In terms of certainty they assigned three stars to this statement, which one meaning low confidence and five meaning virtually certain.[1]
  • The second IPCC report stated that: "No strong reasons have emerged to change these estimates of the climate sensitivity" [2]
  • The third IPCC report states that: "Climate sensitivity is likely to be in the range of 1.5 to 4.5°C. This estimate is unchanged from the first IPCC AssessmentReport in 1990 and the SAR" [3]. This report was the first to give an estimate of the transient climate reponse (TCR).
  • From AR4: "It is likely to be in the range 2°C to 4.5°C with a best estimate of about 3°C, and is very unlikely to be less than 1.5°C. Values substantially higher than 4.5°C cannot be excluded, but agreement of models with observations is not as good for those values." In this report likely is formally defined as being more than 66% likely. Very unlikely <10%.[4]
  • From AR5: "The equilibrium climate sensitivity (ECS) is likely in the range 1.5°C to 4.5°C, extremely unlikely less than 1°C, and very unlikely greater than 6°C." Extremely unlikely is defined as less than 5% probable.[5]
Date
Source Own work
Author Femkemilene

Licensing

I, the copyright holder of this work, hereby publish it under the following license:
w:en:Creative Commons
attribution share alike
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
  • share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
  1. ↑ IPCC FAR WG1, 1990, p. 135
  2. ↑ IPCC AR2 WG1, 1995, p 34
  3. ↑ IPCC TAR WG1, 2001 p. 67
  4. ↑ IPCC AR4 WG1 SPM, 2007 p.12
  5. ↑ IPCC AR5 SYN, 2014, p62

Captions

Estimates of climate sensitivity by different assessments reports of the IPCC

Items portrayed in this file

depicts

inception

20 March 2019

media type

image/png

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current21:18, 20 March 2019Thumbnail for version as of 21:18, 20 March 20191,647 × 1,145 (62 KB)FemkeUser created page with UploadWizard
The following pages on the English Wikipedia use this file (pages on other projects are not listed):

Metadata

This file contains additional information, probably added from the digital camera or scanner used to create or digitize it.

If the file has been modified from its original state, some details may not fully reflect the modified file.

Retrieved from "https://en.wikipedia.org/wiki/File:ECS_assessments_IPCC.png"