Given the inherent uncertainties in predicting how climate and environments will respond to anthropogenic emissions of greenhouse gases, it would be beneficial to society if science could identify geological analogues to the human race’s current
grand climate experiment
. This has been a focus of the geological and palaeoclimate communities over the last 30 years, with many scientific papers claiming that intervals in Earth history can be used as an analogue for future climate change. Using a coupled ocean–atmosphere modelling approach, we test this assertion for the most probable pre-Quaternary candidates of the last 100 million years: the Mid- and Late Cretaceous, the Palaeocene–Eocene Thermal Maximum (PETM), the Early Eocene, as well as warm intervals within the Miocene and Pliocene epochs. These intervals fail as true direct analogues since they either represent equilibrium climate states to a long-term CO
2
forcing—whereas anthropogenic emissions of greenhouse gases provide a progressive (transient) forcing on climate—or the sensitivity of the climate system itself to CO
2
was different. While no close geological analogue exists, past warm intervals in Earth history provide a unique opportunity to investigate processes that operated during warm (high CO
2
) climate states. Palaeoclimate and environmental reconstruction/modelling are facilitating the assessment and calculation of the response of global temperatures to increasing CO
2
concentrations in the longer term (multiple centuries); this is now referred to as the Earth System Sensitivity, which is critical in identifying CO
2
thresholds in the atmosphere that must not be crossed to avoid dangerous levels of climate change in the long term. Palaeoclimatology also provides a unique and independent way to evaluate the qualities of climate and Earth system models used to predict future climate.
It is commonly supposed that a very substantial volume of early basalt magmatism effused synchronously on Siberia platform and West Siberia in a very short time interval at 249.4 ± 0.5 Ma (Reichow et al., 2002, etc.). This magmatism and induced climate change are considered as a main reason of the most catastrophic in the Earth history extinction at the border of Permian and Triassic time. But these conclusions were based on incomplete and unrepresentative data on West Siberia. We have obtained by analysis of pyroxenes monofraction from kainotype basalts of Guslinskaya P-430 well Ar-Ar age 268.4 ± 7.5 Ma. In Taurovskaya 503 well this age is 268.1 ± 7.5 Ma. Hence, volcanism in axial rift zones of the basement of West Siberia plate began earlier than that considered before and significantly earlier than on Siberia platform.
‘Doom’, ‘danger’ and ‘disregard’ are palpable sentiments in recent writing by historical geographers and give the subfield some decidedly political intonations. These three words have diverse, disquieting and expectant connotations and are tracked in this report through clusters of research on colonialism, racism, decolonisation, climate change, Earth history and political reaction and populism. This range of historical work within geography provokes more general questions about how the discipline, generally, sees itself today and at a time of profound uncertainty about the meaning and direction of history. At this time, it is easy to be despondent but vital to hope and work for change.
Climate change is undeniable The pace of global climate change is much higher than observed in the geological past. Recently compiled data indicated that the current global temperature shift is significantly higher than ever recorded in earth history
HOW VARIATIONS IN THE RATES OF EFFUSIVE BASALTIC FLOOD VOLCANISM VERSUS AEROSOL-FORMING EXPLOSIVE VOLCANISM HAVE DRIVEN CLIMATE CHANGE AND RATES OF MASS EXTINCTION THROUGHOUT EARTH HISTORY AND HOW HUMANS HAVE MODIFIED THIS INTERACTION
