Australia overdoes carbon reduction by 294mt: could cool world by 0.0002C extra (maybe)

by JoNova, January 3, 2018


Other countries are failing to meet their targets, but we’re not only achieving them, we’re overdoing it. And this is despite our obvious handicaps: like that we have rapid population growth, are further from everywhere and anywhere* except for Antarctica, and we’re the largest coal exporter in the world;

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Tamper, tamper! How They failed to hide the gulf between predicted and observed warming

by Christopher Monckton,  January 3, 2018, in WUWT


The indefatigable Roy Spencer at the University of Alabama at Huntsville is the first to declare the global temperature anomaly for December 2017. As Fig. 1 shows, in the 39 years 1 month from December 1978 to December 2017, the planet has warmed by half a Celsius degree. But that is equivalent to 1.28 C°/century, or little more than one-third of the 3.3 C°/century predicted with “substantial confidence” by IPCC in 1990 and also by the fifth-generation general-circulation models of the Climate Model Intercomparison Project in 2013.

Ocean surface temperature variability: Large model–data differences at decadal and longer periods

by T Laepple and P Huybers, July 14, 2014 in PNAS


Determining magnitudes of sea surface temperature variability is important for attributing past and predicting future changes in climate, and generally requires the use of proxies to constrain multidecadal and longer timescales of variability. We report a multiproxy estimate of sea surface temperature variability that is consistent between proxy types and with instrumental estimates but strongly diverges from climate model simulations toward longer timescales. At millennial timescales, model−data discrepancies reach two orders of magnitude in the tropics, indicating substantial problems with models or proxies, or both, and highlighting a need to better determine the variability of sea surface temperatures.

Impact of Volcanic Eruptions on Decadal to Centennial Fluctuations of Arctic Sea Ice Extent during the Last Millennium and on Initiation of the Little Ice Age

by J Slawinska and A Robock, November 29, 2017 in AmerMeteorSoc


We evaluate different hypotheses of the origin of the Little Ice Age, focusing on the long-term response of Arctic sea ice and oceanic circulation to solar and volcanic perturbations. We analyze the Last Millennium Ensemble of climate model simulations carried out with the Community Earth System Model at the National Center for Atmospheric Research. We examine the duration and strength of volcanic perturbations, as well as initial and boundary conditions such as the phase of the Atlantic Multidecadal Oscillation, and their impact on decadal to multi-centennial perturbations of the cryospheric, oceanic, and atmospheric components of the climate system.