Skip to content
Climate Claim Checker

Dev claim · claim-2787 · #133 of 154

“Hansen's 1988 results are evidence that the actual climate sensitivity is about 3°C for a doubling of atmospheric CO2.”

Claim tags (sorted stems; highlighted when a passage shares them)

  • actual
  • atmospher
  • climat
  • doubl
  • evid
  • hansen
  • result
  • sensit

Annotators’ label

Disputed Run this claim live

The model’s verdict

The Transformer retrained from the notebook (the 2024 weights were never saved), shown three ways. The first is how the notebook evaluated it.

Notebook protocol

Dev claims predicted in batches of 16, in file order, from the 2024 retrieved evidence, as the notebook does.

Supports✗ differs from the label
Supports
61.7%
Refutes
29.6%
Not enough info
1.4%
Disputed
7.3%

One claim at a time

The same model run on a single claim, which is how the Try-it page runs it.

Supports✗ differs from the label
Supports
54.0%
Refutes
32.4%
Not enough info
8.6%
Disputed
5.0%

With gold evidence

Fed the human-annotated evidence instead of retrieved passages. This is the 'val accuracy' the training loop reports.

Supports✗ differs from the label
Supports
42.4%
Refutes
12.2%
Not enough info
30.7%
Disputed
14.6%

Retrieved vs gold evidence

Gold passages were picked by the dataset’s annotators. Retrieved passages are what the TF-IDF rule returned from all 1.19M passages. Switch between the submitted 2024 output and the re-runs.

2024 submission

The passages the team actually retrieved and submitted in 2024 (their saved output file). The file records only passage ids, so scores are recomputed with the submission rule.

Path
not recorded
Found
0 of 3 gold
P
0.00
R
0.00
F
0.00
  1. #1evidence-16169

    In 2013, Hansen authored a paper called "Climate sensitivity, sea level and atmospheric carbon dioxide," in which he estimated climate sensitivity to be (3±1)°C based on Pleistocene paleoclimate data.

    • hansen (shared with the claim)
    • dioxid
    • sensit (shared with the claim)
    • pleistocen
    • climat (shared with the claim)
    cos
    0.582
    overlap
    0.600
    score
    1.182
    shared
    3

Gold evidence (3)

  1. evidence-632574

    Without feedbacks the radiative forcing of approximately 3.7 W/m2, due to doubling CO 2 from the pre-industrial 280 ppm, would eventually result in roughly 1 °C global warming.

    • w
    • radi
    • roughli
    • feedback
    • pre
    • ppm
  2. evidence-918450

    The equilibrium climate sensitivity (ECS) refers to the equilibrium change in global mean near-surface air temperature that would result from a sustained doubling of the atmospheric equivalent CO 2 concentration (ΔT2×).

    • atmosph
    • equiv
    • equilibrium
    • concentr
    • sensit (shared with the claim)
    • sustain
    • ec
  3. evidence-692256

    In his first paper on the matter, he estimated that global temperature would rise by around 5 to 6 °C (9.0 to 10.8 °F) if the quantity of CO 2 was doubled.

    • quantiti
    • co
    • temperatur
    • rise
    • paper
    • global
    • matter
    • doubl (shared with the claim)
    • estim

Optional · uses your own API key

Second opinion from an LLM

The model reads this claim and the evidence passages shown on this page, picks one of the four verdicts and cites the passages it used. It is told to judge from the passages only. You review the answer; the call and your decision go to the AI audit log in this browser.

Evidence to send

Without a key nothing is sent anywhere. The rest of the site does not need one.