Claim: Doubling the concentration of atmospheric CO2 from its pre-industrial level, in the absence of other forcings and feedbacks, would likely cause a warming of ~0.3°C to 1.1°C.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: The higher CO2 levels led to an additional climate warming ranging between 0.1° and 1.5 °C.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: 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.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: Increased concentrations of gases such as CO 2 (~20%), ozone and N 2O are external forcing on the other hand.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: Global warming will likely rise to 1.5°C above pre-industrial levels between 2030 and 2052 if warming continues to increase at the current rate.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: The global temperature increase since the beginning of the industrial period (taken as 1750) is about 0.8 °C (1.4 °F), and the radiative forcing due to CO 2 and other long-lived greenhouse gases – mainly methane, nitrous oxide, and chlorofluorocarbons – emitted since that time is about 2.6 W/m2.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to 1.7 °C (0.5 to 3.1 °F) in a moderate scenario, or as much as 2.6 to 4.8 °C (4.7 to 8.6 °F) in an extreme scenario, depending on the rate of future greenhouse gas emissions and on climate feedback effects.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: Climate sensitivity is defined as the amount of global average surface warming following a doubling of carbon dioxide concentrations.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: In the 1998 paper, "CO2-induced global warming: a skeptic's view of potential climate change" Idso said: "Several of these cooling forces have individually been estimated to be of equivalent magnitude, but of opposite sign, to the typically predicted greenhouse effect of a doubling of the air’s CO2 content, which suggests to me that little net temperature change will ultimately result from the ongoing buildup of CO2 in Earth's atmosphere.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: The 2 °C rise is typically associated in climate models with a carbon dioxide equivalent concentration of 400–500 ppm by volume; the current (January 2015) level of carbon dioxide alone is 400 ppm by volume, and rising at 1–3 ppm annually.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: In a scenario where global emissions start to decrease by 2010 and then declined at a sustained rate of 3% per year, the likely global average temperature increase was predicted to be 1.7 °C above pre-industrial levels by 2050, rising to around 2 °C by 2100.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: The IPCC (2007) estimates that the expected rise in temperature due to a doubling of CO2 to be about 3 °C (5.4 °F), ± 1.5°.