Isotopi Idrogeno

History of Climate Change

Theories and opinions about climate change abound – from those claiming human-induced climate change is already beyond control to those who express scepticism about the real extent of these changes. How should we weigh up the scientific evidence, and what role does climate change play in the history of the Earth? In this comprehensive history of the climate and climate change, Antonello Provenzale explains how the planetary climate system works and how the climate has evolved over millions of years. Starting from the catastrophic events that marked the early history of the Earth, including seas of magma, global glaciations and mass extinctions, he demonstrates how the climate has fluctuated between hot and cold periods, with the Earth hot and lush with forests at certain times and almost entirely covered by a thick layer of ice at others. The mechanisms that determine the modifications of the climate are multiple and complex and include external factors, such as solar luminosity and variations in the Earth's orbit, as well as internal processes connecting the atmosphere, the oceans, the crust, the mantle and the biosphere, composed of living organisms. While the climate has fluctuated a great deal over the Earth’s long history, there are two features of our current situation that are a source of real concern. First, the rise in temperature of the last fifty years has been extremely fast, making it difficult for the environment to adapt to the new conditions. Second, the human population is much greater than it was in the past, and this population needs water, food, energy and shelter to survive and flourish. If temperatures continue to rise as they have in recent decades, ours will not be an easy world in which to live. To appreciate what is at stake, we need to understand how the climate works and how human activity is affecting it – not in order to save the planet, which will do just fine on its own and probably better without us, but to save ourselves.

Bericht

Muonic Atoms and Molecules

From Sunday evening, April 5, until Thursday afternoon, April 9, 1992,49 scientists from 10 countries met at the Centro Stefano Franscini on Monte VeritA overlooking Ascona, in the state of Ticino in Switzerland, for an international workshop on Muonic Atoms and Molecules. More than two-thirds of the participants presented their results in talks of 20 to 40 minutes' duration. In addition, Prof. Gabriele Torelli gave, under the patronage of the Ministro del Ambiente of the state of Ticino, Dr. Mario Camani, a lecture in Italian entitled "Un modo insolito di studiare Ie proprieta nucleari, atomiche e chimiche". The scientific program commenced on Monday morning with discussions centering on nuclear muon capture and nuclear fusion and fission, moving on to muonic atom spectroscopy in the afternoon. All of Tuesday was devoted to muon catalyzed fusion and muon transfer. On Wednesday morning, different aspects of hot muonic atoms were discussed, followed by informal gatherings in the afternoon and evening. On Thursday morning we took a look at the prospects for the TRIUMF and PSI meson factories, and new experimental methods. The conference was brought to a close in the afternoon with C.P. summarizing the events of the past days. The two organizers want to thank all participants for their contributions and for the lively discussions which often followed the different talks.