Planetary obliquity determines the meridional distribution of annual mean insolation. For obliquity exceeding 55◦, the weakest insolation occurs at the equator. Stable partial snow and ice cover on such a planet would be in the form of a belt about the equator rather than polar caps. An analytical model of planetary climate is used to investigate the stability of ice caps and ice belts over the...

[1] For most of the Northern Hemisphere Ice Ages, from 3.0 to 0.8 m.y., global ice volume varied predominantly at the 41,000 year period of Earth’s orbital obliquity. However, summer (or summer caloric half year) insolation at high latitudes, which is widely believed to be the major influence on high-latitude climate and ice volume, is dominated by the 23,000 year precessional period. Thus the ...

Actual and insolation-weighted Northern Hemisphere snow cover and sea ice are binned by latitude bands for the years 1973–2002. Antarctic sea-ice is also analyzed for the years 1980–2002. The use of insolation weighting provides an improved estimate of the radiative feedbacks of snow cover and sea-ice into the atmosphere. One conclusion of our assessment is that while a decrease in both areal a...

Abstract Whether the South Asian summer monsoon (SASM) is controlled by local or remote insolation at orbital band remains uncertain. Here, we perform a transient simulation forced Earth's parameters between 400 and 350 ka BP, period characterized significant contrast insolation, to identify SASM's response forcing. Simulation results suggest that primary driver of orbital‐scale SASM variabilit...

Our limited understanding of the climate controls on tropical forest seasonality is one of the biggest sources of uncertainty in modeling climate change impacts on terrestrial ecosystems. Combining leaf production, litterfall and climate observations from satellite and ground data in the Amazon forest, we show that seasonal variation in leaf production is largely triggered by climate signals, s...

We describe the development of new, Web-based maps of insolation and photovoltaic energy potential across Canada. The maps will be made available on the Natural Resources Canada website. They are presented for each month and summed for the entire year, for five different surface orientations: a suntracking orientation and four fixed South-facing orientations with latitude, vertical and latitude...

[1] The Milankovitch hypothesis is widely held to be one of the cornerstones of climate science. Surprisingly, the hypothesis remains not clearly defined despite an extensive body of research on the link between global ice volume and insolation changes arising from variations in the Earth’s orbit. In this paper, a specific hypothesis is formulated. Basic physical arguments are used to show that...