Sentences with phrase «ar4 warming projections»

In Addendum: Climate Change Impacts in the United States (pp. 26 - 28), Michaels and his colleague Chip Knappenberger discuss those studies in greater detail and also illustrate with two graphs how the IPCC AR4 warming projections should be adjusted in light of more recent climate sensitivity research.

Not exact matches

The Copenhagen Diagnosis authors used IPCC Fourth Assessment Report (AR4) projections as well as post-AR4 analysis to estimate that emissions reductions of around 40 % from industrial nations are needed to make it likely to keep global warming below 2 °C.

Note that the «long, fat tail» of high - end warming projections in AR4 is absent from projections based on more recent science.

We can therefore again compare the Scenario A2 multi-model global surface warming projections to the observed warming, in this case since 2000, when the AR4 model simulations began (Figure 9).

As we will show below, this is due to the preponderance of natural temperature influences being in the cooling direction since 2000, while the AR4 projection is consistent with the underlying human - caused warming trend.

First of all, IPCC has made specific projections of anticipated warming, both in the TAR in 2001 (based on 2000 data) and in AR4 in early 2007 (based on 2005 data).

It would have been more clear to state that this projection of warming from the AR4 applied to the first two decades, such as in this statement of the IPCC

I do not understand why IPCC can not simply concede that its earlier warming projections (in TAR and AR4) were wrong, adding explanatory notes about natural variability, etc. to explain why the projections were wrong.

Also, I am missing a specific statement that acknowledges that the short - term warming projections of TAR (0.15 ° to 0.3 °C per decade) and AR4 (0.2 °C per decade) turned out to be wrong, i.e. there has been no warming since the end of 2000, despite unabated human GHG emissions and atmospheric concentrations reaching record levels.

The projected future warming projections (for the end of this century) have been reduced a bit, starting from essentially the same base (AR5: 1986 - 2005 = +0.26 °C versus AR4: 1980 - 1999 = +0.23 °C):

The «pause» and the many observation - based studies showing a much lower 2xCO2 ECS than previously predicted by the models cited by IPCC in AR4, gave IPCC the possibility for a paradigm shift to refocus away from its CAGW premise to one of reduced warming projections based on the lower observed CO2 sensitivity.

I concluded that the projections of extreme sea level rise are not consistent with plausible physical mechanisms, not supported by the available data, and further, that the AR4 projected range (about 30 - 50 cm by 2100) agreed perfectly with my projections over a wide range of warming scenarios.