Ice Caps and Glaciers

It seems that the poles are warming faster than the rest of the planet. It was believed that because of the tilt of the Earth s axis, the North Pole was melting faster. This is disputed by the March 2008 report of the British Antarctic Survey that reported the fracture of the Wilkins floating ice shelf at the South Pole, which is the size of the state of Connecticut. 

The World Glacier Monitoring Service at the University of Zurich reviewed 30 glaciers in 9 mountain regions, including the moving frozen rivers of the Andes, Himalayas, and elsewhere. Its members concluded that the loss of glaciers will reduce summertime sources of river water and therefore will 

Post-Oil Energy Technology After the Age of Fossil Fuels 

Measurements in Bermuda and the Bahamas indicate that before the last ice age (130,000 years ago), corals flourished 20 feet above today s sea level. Such high sea levels could have been caused by the melting of the West Arctic Ice Sheet and the ice on Greenland. 

All this does not mean that the combination of human and natural influences on ice cap formation is easy to understand after all, satellite observation of polar ice started only in 1979, and the ice cap area around Antarctica is at record highs. Yet, for the first time, scientists have confirmed that the ice on Earth is melting at both ends. How is that possible How can the southern ice cap grow and the ice be melting at both ends It seems that the area of the southern ice cap is growing because of increased humidity in the air, and its thickness is dropping because of the warming of the waters below. 

---

Water is among the most important compounds on earth. It is the main constituent of the hydrosphere, which along with the mantle, crust, and the atmosphere are the four components of our planet. It is present everywhere on earth and is essential for sustenance of life. Water also determines climate, weather pattern, and energy balance on earth. It also is one of the most abundant compounds. The mass of all water on earth is l.dxlO i kg and the total volume is about l.dxlO km, which includes 97.20% of salt water of oceans, 2.15% of fresh water in polar ice caps and glaciers, 0.009% in freshwater lakes, 0.008% in saline lakes, 0.62% as ground waters, 0.005% in soil moisture 0.0001% in stream channels and 0.001% as vapors and moisture in the atmosphere. 

Inorganic chemistry draws its strength from its great practical utility, and this book presents the subject from the standpoint of applications rather than the customary one of quantum mechanical bonding theory. Since the quintessential subject matter is the properties of the 112 known chemical elements and their compounds, we begin with a consideration of the availability of the commonest elements in the Earth s crust (Table 1.1), hydrosphere (i.e., oceans, lakes, rivers, snowfields, ice caps, and glaciers), and atmosphere, along with brief summary of the production and uses of these elements and their compounds. 

About 97.2 percent of Earth s water is saline (salty) ocean water. Another 2.14 percent is fresh water frozen in polar ice caps and glaciers. All the remaining water, less than 1 percent of Earth s total, comprises water vapor in the atmosphere, water in the ground, and water in rivers and lakes—the fresh water we rely on in our daily lives. 

A Nearly three-fourths of the earth s surface is covered with water, and about 2% of the total is in the form of polar ice caps and glaciers. 

Approximately 97.3% of the world s vast supply of water is in the oceans. Most of the rest is in the form of polar ice caps and glaciers (2.0%) and underground fresh water (0.6%). Freshwater lakes and rivers account for less than 0.01% of the total, yet they nevertheless contain an enormous amount of water (1.26 X 1014 m3). 

As the world s population continues to grow, the demand for fresh water will certainly increase. Seventy five percent of the Earth s surface is covered with water. Out of this 75%, almost 97% of the world s water is salty and not readily drinkable. The other 2% is locked as solids, in the form of ice caps and glaciers, leaving us with about 1% of freshwater that is available for all humanity s need. This small amount of freshwater can be found in the form of surface water and groundwater. Of the 1% of freshwater available, 96% is in the form of groundwater. From 1940 to 1990, withdrawals of fresh water from rivers, lakes, reservoirs, and other sources have been augmented fourfold [28]. 

If the total available surface freshwater supply of some 126,000 km, which excludes the ice caps and glaciers, was evenly distributed over the total nonfrozen land area of the Earth, it would amount to only some 1.1 m in depth. Addition of the net annual land-based precipitation, after evaporation, would add only a further 0.8 m in the depth. The combined total certainly does not represent a limitless resource to serve the agricultural, industrial, and personal needs of a world population of almost six billion. 

Water, in its three phases, liquid water, ice and water vapour, is highly abundant at the Earth s surface, having a volume of 1.4 billion km3. Nearly all of this water (>97%) is stored in the oceans, while most of the rest forms the polar ice-caps and glaciers (Table 1.1). Continental freshwaters represent less than 1% of the total volume, and most of this is groundwater. The atmosphere contains comparatively little water (as vapour) (Table 1.1). Collectively, these reservoirs of water are called the hydrosphere. 

Other approximate reservoir residence times include 10 years for lakes and reservoirs, 2 weeks for rivers, and 10 to thousands of years for ice caps and glaciers. 

At no time has the world faced such an acute shortage of potable water than today. This is despite the fact that 75% of the world s surface is covered with water. Unfortunately, 97% of this water is saline and therefore undrinkable. Of the available fresh water, 2% is locked up in ice caps and glaciers. Hence there is only about 1% of water available to meet human needs. 

The general composition of the various types of water in the hydrosphere can best be discussed within the framework of the hydrologic cycle. Of the total amount of water on the earth the oceans account for the vast majority 97,13 percent. The polar ice caps and glaciers contain 2.24 percent groundwater accounts for 0.61 percent and the rivers, lakes, and streams contain only 0,02 percent of the total. 

Water can universally be found in the solid, gaseous, and liquid states. Saltwater oceans contain about 96.5% of our global water supply. Ice, the solid form of water, is the most abundant form of freshwater and most of it, nearly 68.7%, is currently trapped in the polar ice caps and glaciers [1]. About 30% of the freshwater sources are present in aquifers as groundwater. The remaining freshwater is surface water in lakes and rivers, soils, wetlands, biota, and atmospheric water vapor. 

Seawater is the largest source of available water. It is estimated that only 2.5% of the earth s 1.4 billion km of water is fresh water, and 69% of that is in the form of ice olar ice caps and glaciers) or in underground aquifers too deep to tap. The amount of fresh water that is available is essentially fixed, and as the population continues to grow, the per capita availability shrinks. Seawater, on the other hand, is available in essentially unlimited quantities in die foreseeable future, and is still relatively unpolluted compared with natural fresh water sources many regions of die world. 

What percentage of Earth s total water supply is freshwater What percentage of Earth s freshwater is in ice caps and glaciers What percentage of Earth s total water is readily available for human use ... 

About 97% of Earth s water is in the oceans. This saline water contains vast amounts of dissolved minerals. More than 70 elements have been detected in the mineral content of seawater. Only four of these—chlorine, sodium, magnesium, and bromine—are now commercially obtained from the sea. The world s fresh water comprises the other 3%, of which about two-thirds is locked up in polar ice caps and glaciers. The remaining fresh water is found in groundwater, lakes, rivers, and the atmosphere. 

Sea-level rise in the tropical Pacific and Indian Oceans has been studied in recent years. The sea level is influenced by thermal expansion of the oceans from the warmer temperatures, melting polar ice caps and glaciers, and the atmospheric changes caused by El Nino. Large variability during El Nino years and the shortness of many of the individual tide-gauge records contribute to uncertainty of historical rates of sea-level rise. 

Unfortunately, 97% of the water on Earth is salt water, leaving only 3% as fresh water, of which more than two-thirds is frozen in polar ice caps and glaciers. The remaining unfrozen fresh water for direct use as a human resource is mainly found as groundwater (Table 5.4.4). 

The majority of fresh water is used for irrigation, that is, for agricultural use (70%), and 15% is needed industrially. Unfortunately, 97% of water on the Earth is salt water, leaving only 3% as fresh water, of which more than two-thirds is frozen in polar ice caps and glaciers. The remaining unfrozen fresh water for direct use as a human resource is found mainly as groundwater. The demand for fresh water already exceeds supply in many parts of the world and, as the world population continues to rise, this situation may intensify in future. Today, 13% of the global population lacks access to improved water sources, and 38% lacks access to improved sanitation. 

---