Books on the topic 'Surface melting'

Situated at the southern edge of the Tibetan Plateau (TP), the Hindu-Kush-Himalayas-Gangetic (HKHG) region is under the clear and present danger of climate change. Flash-flood, landslide, and debris flow caused by extreme precipitation, as well as rapidly melting glaciers, threaten the water resources and livelihood of more than 1.2 billion people living in the region. Rapid industrialization and increased populations in recent decades have resulted in severe atmospheric and environmental pollution in the region. Because of its unique topography and dense population, the HKHG is not only a major source of pollution aerosol emissions, but also a major receptor of large quantities of natural dust aerosols transported from the deserts of West Asia and the Middle East during the premonsoon and early monsoon season (April–June). The dust aerosols, combined with local emissions of light-absorbing aerosols, that is, black carbon (BC), organic carbon (OC), and mineral dust, can (a) provide additional powerful heating to the atmosphere and (b) allow more sunlight to penetrate the snow layer by darkening the snow surface. Both effects will lead to accelerated melting of snowpack and glaciers in the HKHG region, amplifying the greenhouse warming effect. In addition, these light-absorbing aerosols can interact with monsoon winds and precipitation, affecting extreme precipitation events in the HKHG, as well as weather variability and climate change over the TP and the greater Asian monsoon region.

This is an advance summary of a forthcoming article in the Oxford Encyclopedia of Planetary Science. Please check back later for the full article.Mars, which has a tenth of the mass of Earth, has cooled as a single lithospheric plate. Current topography gravity maps and magnetic maps do not show signs of the plate tectonics processes that have shaped the Earth’s surface. Instead, Mars has been shaped by the effects of meteorite bombardment, igneous activity, and sedimentary—including aqueous—processes. Mars also contains enormous igneous centers—Tharsis and Elysium, with other shield volcanoes in the ancient highlands. In fact, the planet has been volcanically active for nearly all of its 4.5 Gyr history, and crater counts in the Northern Lowlands suggest that may have extended to within the last tens of millions of years. Our knowledge of the composition of the igneous rocks on Mars is informed by over 100 Martian meteorites and the results from landers and orbiters. These show dominantly tholeiitic basaltic compositions derived by melting of a relatively K, Fe-rich mantle compared to that of the Earth. However, recent meteorite and lander results reveal considerable diversity, including more silica-rich and alkaline igneous activity. These show the importance of a range of processes including crystal fractionation, partial melting, and possibly mantle metasomatism and crustal contamination of magmas. The figures and plots of compositional data from meteorites and landers show the range of compositions with comparisons to other planetary basalts (Earth, Moon, Venus). A notable feature of Martian igneous rocks is the apparent absence of amphibole. This is one of the clues that the Martian mantle had a very low water content when compared to that of Earth.The Martian crust, however, has undergone hydrothermal alteration, with impact as an important heat source. This is shown by SNC analyses of secondary minerals and Near Infra-Red analyses from orbit. The associated water may be endogenous.Our view of the Martian crust has changed since Viking landers touched down on the planet in 1976: from one almost entirely dominated by basaltic flows to one where much of the ancient highlands, particularly in ancient craters, is covered by km deep sedimentary deposits that record changing environmental conditions from ancient to recent Mars. The composition of these sediments—including, notably, the MSL Curiosity Rover results—reveal an ancient Mars where physical weathering of basaltic and fractionated igneous source material has dominated over extensive chemical weathering.

The climate of our planet is changing at a rate unprecedented in recent human history. The energy absorbed from the sun exceeds what is returned to space. The planet as a whole is gaining energy. The heat content of the ocean is increasing; the surface and atmosphere are warming; mid-latitude glaciers are melting; sea level is rising. The Arctic Ocean is losing its ice cover. None of these assertions are based on theory but on hard scientific fact. Given the science-heavy nature of climate change, debates and discussions have not played as big a role in the public sphere as they should, and instead are relegated to often misinformed political discussions and inaccessible scientific conferences. Michael B. McElroy, an eminent Harvard scholar of environmental studies, combines both his research chops and pedagogical expertise to present a book that will appeal to the lay reader but still be grounded in scientific fact. In Energy and Climate: Vision for the Future, McElroy provides a broad and comprehensive introduction to the issue of energy and climate change intended to be accessible for the general reader. The book includes chapters on energy basics, a discussion of the contemporary energy systems of the US and China, and two chapters that engage the debate regarding climate change. The perspective is global but with a specific focus on the US and China recognizing the critical role these countries must play in addressing the challenge of global climate change. The book concludes with a discussion of initiatives now underway to at least reduce the rate of increase of greenhouse gas emissions, together with a vision for a low carbon energy future that could in principle minimize the long-term impact of energy systems on global climate.

Though not traditionally thought of as strategic natural resources, glaciers are a crucial part of our global ecosystem playing a fundamental role in the sustaining of life around the world. Comprising three quarters of the world's freshwater, they freeze in the winter and melt in the summer, supplying a steady flow of water for agriculture, livestock, industry and human consumption. The white of glacier surfaces reflect sunrays which otherwise warm our planet. Without them, many of the planet's rivers would run dry shortly after the winter snow-melt. A single mid-sized glacier in high mountain environments of places like California, Argentina, India, Kyrgyzstan, or Chile can provide an entire community with a sustained flow of drinking water for generations. On the other hand, when global temperatures rise, not only does glacier ice wither away into the oceans and cease to act as water reservoirs, but these massive ice bodies can become highly unstable and collapse into downstream environments, resulting in severe natural events like glacier tsunamis and other deadly environmental catastrophes. But despite their critical role in environmental sustainability, glaciers often exist well outside our environmental consciousness, and they are mostly unprotected from atmospheric impacts of global warming or from soot deriving from transportation emissions, or from certain types of industrial activity such as mining, which has been shown to have devastating consequences for glacier survival. Glaciers: The Politics of Ice is a scientific, cultural, and political examination of the cryosphere -- the earth's ice -- and the environmental policies that are slowly emerging to protect it. Jorge Daniel Taillant discusses the debates and negotiations behind the passage of the world's first glacier-protection law in the mid-2000s, and reveals the tension that quickly arose between industry, politicians, and environmentalists when an international mining company proposed dynamiting three glaciers to get at gold deposits underneath. The book is a quest to educate general society about the basic science behind glaciers, outlines current and future risks to their preservation, and reveals the intriguing politics behind glacier melting debates over policies and laws to protect the resource. Taillant also makes suggestions on what can be done to preserve these crucial sources of fresh water, from both a scientific and policymaking standpoint. Glaciers is a new window into one of the earth's most crucial and yet most ignored natural resources, and a call to reawaken our interest in the world's changing climate.