H

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Hydrogen Bonding

at: code.enthought.com/.../mayavi/auto/examples.html

The water trimer has a chiral cyclic equilibrium structure with each water monomer acting as a single hydrogen bond donor and acceptor (75, 98)

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

Two distinct tunneling pathways rearrange the hydrogen bond pattern in the cyclic water trimer

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

The water tetramer has a highly symmetric homodromic S4 equilibrium structure resulting in oblate symmetric top spectra with no vibrational averaging required

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

The high symmetry of the tetramer requires highly concerted tunneling motions and limits the number of degenerate minima that can be connected on the IPS via feasible tunneling

motions to two

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

The water hexamer has been determined to have a cage structure with the oxygens forming a distorted octahedron

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

e at: witcombe.sbc.edu/water/chemistryproperties.html

e at: witcombe.sbc.edu/water/chemistryproperties.html

image at: sciencechicagoblog.com/.../question-about-water/

What has happened is that there has been a charge in the dipole moment

dμ/dt ≠ 0

The water trimer has a chiral cyclic equilibrium structure with each water monomer acting as a single hydrogen bond donor and acceptor (75, 98)

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

Two distinct tunneling pathways rearrange the hydrogen bond pattern in the cyclic water trimer

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

The water tetramer has a highly symmetric homodromic S4 equilibrium structure resulting in oblate symmetric top spectra with no vibrational averaging required

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

The high symmetry of the tetramer requires highly concerted tunneling motions and limits the number of degenerate minima that can be connected on the IPS

via feasible tunneling motions to two

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

The water hexamer has been determined to have a cage structure with the oxygens forming a distorted octahedron

Keutsch F N, Saykally R J PNAS 2001;98:10533-10540

©2001 by The National Academy of Sciences

yedda.com

image at: www.meta-synthesis.com/.../LAB_matrix.html

The Antarctic Ice SheetThe Antarctic Ice Sheet is a thick, ancient sheet of ice with a maximum depth of nearly 3 miles (15,000 feet). It is the iceberg 'factory' of the Southern Ocean. This icesheet contains over 5 million cubic miles (30 million cubic km) of ice. The weight of the Antarctic ice is so great that in many areas it actually pushes the land below sea-level. Without its ice cover Antarctica would eventually rise up another 1500 feet (450 m) above sea-level. The Ice Sheet is very gradually moving, in this case towards the sea in a radial pattern.

With 98% of its surface covered with various forms of snow and ice, it's no wonder that the continent of Antarctica attracts "cold weather" scientists from all over the world. Basically, Antarctica is a snow and ice "factory" with ice depths on the Polar Plateau reaching 15,000 feet (the continent's average ice thickness is 7,000 feet). Thus, one of Antarctica's most important resources is its ice. It is said that Antarctica's ice accounts for 70% of the world's fresh water. Some people have considered towing icebergs from Antarctica to parts of the world in need of fresh water.As strange as it sounds, however, Antarctica is essentially a desert. The average yearly total precipitation is about two inches. So, where did all this snow and ice come from? The answer lies in Antarctica's unique location at the bottom of the world and the unique weather conditions that exist there.

Antarctica

Area: total: 14 million sq km land: 14 million sq km (280,000 sq km ice-free, 13.72 million sq km ice-covered) (est.) note: fifth-largest continent, following Asia, Africa, North America, and South America, but larger than Australia and the subcontinent of EuropeRank: 7

Physical propertiesFurther information: Sea waterThe area of the World Ocean is 361×106 km2 (139×106 mi2)[6] Its volume is approximately 1.3 billion cubic kilometres (310 million cu mi).[7] This can be thought of as a cube of water with an edge length of 1,111 kilometres (690 mi). Its average depth is 3,790 metres (12,400 ft), and its maximum depth is 10,923 metres (6.787 mi)[6] Nearly half of the world's marine waters are over 3,000 metres (9,800 ft) deep.[3] The vast expanses of deep ocean (anything below 200 metres (660 ft) cover about 66% of the Earth's surface.[8] This does not include seas not connected to the World Ocean, such as the Caspian Sea.The total mass of the hydrosphere is about 1,400,000,000,000,000,000 metric tons (1.5×1018 short tons) or 1.4×1021 kg, which is about 0.023% of the Earth's total mass. Less than 3% is freshwater; the rest is saltwater, mostly in the ocean.

Assuming the average thickness of the ice in Antarctica is 7000 feet estimate the sea level rise if all the ice melted.