• Publications
  • Influence
Mid- to Late Holocene climate change: an overview
The last 6000 years are of particular interest to the understanding of the Earth System because the boundary conditions of the climate system did not change dramatically (in comparison to larger
How Warm Was the Medieval Warm Period?
Abstract A frequent conclusion based on study of individual records from the so-called Medieval Warm Period (∼1000-1300 A.D.) is that the present warmth of the 20 th century is not unusual and
Climate sensitivity constrained by temperature reconstructions over the past seven centuries
An independent estimate of climate sensitivity is found that is very similar to those from instrumental data, and if the latter are combined with the result from all proxy reconstructions, then the 5–95 per cent range shrinks, thus substantially reducing the probability of very high climate sensitivity.
Neoproterozoic ‘snowball Earth’ simulations with a coupled climate/ice-sheet model
Computer simulations of this unusual climate stage with a coupled climate/ice-sheet model and a general circulation model result in an equatorial belt of open water that may have provided a refugium for multicellular animals.
North Atlantic Deep Water cools the southern hemisphere
A standard explanation for coupling climate variations in the northern and southern hemispheres involves fluctuations in North Atlantic Deep Water (NADW) production. However, I suggest that the
Ice Age terrestrial carbon changes revisited
N. Shackleton (1977) first proposed that changes in the marine δ 13 C record (Δδ 13 C) could be used to infer ice age changes in carbon storage on land. The previously published best estimate from
Technical details concerning development of a 1200 yr proxy index for global volcanism
Abstract. This report describes details of developing a volcano forcing reconstruction (Crowley et al., 2008) for climate models that is based primarily on sulphate records in Antarctic and Greenland
Detection of Human Influence on a New, Validated 1500-Year Temperature Reconstruction
Abstract Climate records over the last millennium place the twentieth-century warming in a longer historical context. Reconstructions of millennial temperatures show a wide range of variability,
Simulation of the influence of solar radiation variations on the global climate with an ocean-atmosphere general circulation model
Abstract. Two simulations with a global coupled ocean-atmosphere circulation model have been carried out to study the potential impact of solar variability on climate. The Hoyt and Schatten estimate
Climate and carbon-cycle variability over the last millennium
Abstract. A long-standing task in climate research has been to distinguish between anthropogenic climate change and natural climate variability. A prerequisite for fulfilling this task is the