Abstract Snow albedo is an important climate parameter as it governs the amount of solar energy absorbed by the snow and can be considered a major contributor to the surface radiation budget. The present study deals with the estimation of temporal variation of snow albedo at the upper elevation zone of glaciated Mago Basin of Arunachal Pradesh in eastern Himalaya. Moderate Resolution Imaging Spectroradiometer (MODIS) Daily Snow Products (MOD10A1 and MYD10A1) at 500 m spatial resolution were used. Both the MODIS data for ten years (2003–13) and the Advanced Spaceborne Thermal Emission and Reflection (ASTER) digital elevation model (DEM) of the study area were downloaded from NASA DAAC of NSIDC. The percentage area under different snow types (dry snow, wet snow, firn and ice) was determined by masking the upper elevation zone of the DEM into the albedo images. The average monthly slopes show a decreasing trend in area (%) of dry snow and wet snow and an increasing trend for firn and ice. Dry snow and wet snow cover percentages were observed to be decreasing, whereas firn and ice cover showed an increasing trend for most of the months. Firn dominated the type of snow, followed by ice then wet snow; the smallest area (%) was that of dry snow for the study period.

The world contains abundant energy resources. The challenge is extracting and utilizing these resources affordably, in an environmentally responsible way, and in a dense enough form to be useful to humans. The link between energy, the environment, and the economy is unavoidable and involves the geosciences at its core. Carbon-based fuels such as wood, hay, and coal powered human society for millennia. Then, in the early twentieth century, petroleum in various refined forms came into use for lighting, heating, and early combustion engines. Today, fossil fuels—coal, petroleum products, and natural gas—represent an important 85% of the global energy mix, but they are not without challenges. Coal's greatest challenges are environmental: the impact of surface mining; water contamination; discharge of airborne pollutants including sulfur, nitrogen, and mercury; and the emission of CO 2 . The emerging technologies of carbon capture and sequestration may offer the prospect (such as coal-fired of solving one of coal's problems; large, stationary sources of CO 2 power plants) are the most efficient targets for carbon capture. However, capturing CO 2 is expensive. Oil and, to a much lesser degree, natural gas also produce CO 2 and other emissions when combusted. Oil and natural gas require drilling, entailing the associated environmental impacts of oil-field operations; yet there remain considerable global oil and natural gas resources. The current frontiers for conventional oil and natural gas production include ultra-deep water, the Arctic, sediments deposited beneath major salt formations, and other extreme operational environments. As existing and new conventional oil and natural gas reserves decline, unconventional reservoirs—shale gas, coal bed natural gas, tight gas, shale oil, oil shale, oil sands, and perhaps eventually natural gas hydrates—will represent a growing part of the fossil-fuel mix. Nuclear energy—today fission, and tomorrow, perhaps, fusion—is very dense, has no emissions, is highly efficient, and is very affordable on a kilowatt-hour basis. Adoption of nuclear energy is limited by the high initial cost of building a power plant, public perception, issues of waste handling, the fear of proliferation, and the very real need to make reactors safe from natural and human-caused disasters. “Renewable” forms of energy—those that are generated by “renewable” motion such as wind and moving water; or “renewable” sources of heat such as geothermal and solar; or those that are grown such as biofuels—will increase as a proportion of the energy mix. These sources are currently limited in growth rate by their lower energy density and, for some, their intermittency. Intermittency—the wind does not always blow and the sun does not always shine—must be addressed by significant improvements in energy storage technologies: in chemical batteries; as pumped water or compressed air; as heat stored in molten salt, buildings, and other forms; as kinetic energy in flywheels; as electrons in advanced capacitors; or by various other technologies. But these energy storage technologies need to be made efficient, affordable, and scalable before they will be deployed broadly. Because the transition from a fossil-energy present to an alternate-energy future involves the interplay between energy, environment, economy, and policy, almost without exception all forms of energy involve the geosciences. Coal mining requires geologic understanding. Large-scale geologic carbon sequestration, which might someday make coal more environmentally friendly, will rely on a whole new discipline involving advanced subsurface characterization and monitoring. The subsurface understanding and technology required for conventional and unconventional oil and gas exploration and extraction are substantial. From the scale of nanopores to tectonic plates, the use of advanced seismic imaging, ever more-quantified field and laboratory experimentation, airborne remote sensing, and much more is required to unlock the fossil-fuel resources that remain trapped in the Earth. Nuclear energy relies on sources of uranium, plutonium, thorium, and many other mined products. And eventually, geologic repositories will be required to store the waste products of nuclear power generation. In terms of renewable energy, production of biofuels involves soil science, hydrogeology, fertilizers, weather, and climate. Harnessing geothermal energy involves the ability to characterize the subsurface geothermal resource. Generating power from tides and waves involves oceanography and analysis of coastal change. Utilizing wind depends on weather pattern studies and geomorphology for the siting of turbines, as well as the mining of copper, carbon, and other materials. Producing solar energy involves the geosciences, with the need for silicon, gallium, cadmium, copper, and other materials. As large-scale energy-storage solutions become necessary, input from the geosciences will range from characterizing the subsurface for compressed-air storage to mining rare-earth elements for chemical batteries. The involvement of geosciences in energy does not stop with subsurface understanding or the construction of a power plant. “Above-ground” environmental and policy challenges covering the full lifecycle of any form of energy are as great as the “below-ground” technical challenges. Environmental geologists, biologists, energy economists, and policymakers must come together to develop sensible policies and regulatory rules that make it possible for industry, government, academe, and nongovernmental organizations (NGOs) to work together to deliver balanced solutions.

Abstract This publcation is a comprehensive and integrated review of energy and mineral resources in the Solar System, including materials that can both sustain future manned expeditions and colonies in space and support Earth's energy and critical material challenges in the 21st century and beyond. All long-range programs for human exploration and settlement of the solar system recognize the vital role that extraterrestrial energy and mineral resources must play in support of human habitation of near Earth Space and the Moon, Mars, and the Asteroids. Produced in colaboration with the AAPG Energy Minerals Division and the AAPG Astrogeology Committee, this Memoir reflects AAPG's vision of advancing the science and technology of energy, minerals, and hydrocarbon resources into the future and supporting exploration and development of the ultimate frontier, beyond Earth's atmosphere.

Abstract Exhaustive study of the historical use of energy is paramount in forecasting future use accurately. The much-needed detailed historical statistical data on human population, energy consumption, and current information about present and possible future sources of energy are assembled in this book. The pubication places particular emphasis on the kind of data that allows trends to be established that can be projected far into the future. It provides the foundation for readers to broaden their knowledge about past energy consumption and its sources of supply. It also furnishes a glimpse into the future of how, and how much, energy will be consumed in the 21st century and what sources will most likely supply it.