Current sea level rise has occurred at a mean rate of 1.8 mm per year for the past century,[1][2] and more recently, during the satellite era of sea level measurement, at rates estimated near 2.8 ± 0.4[3] to 3.1 ± 0.7[4] mm per year (1993–2003). Current sea level rise is due significantly to global warming Global warming is the increase in the average temperature of Earth's near-surface air and oceans since the mid-20th century and its projected continuation. According to the 2007 Fourth Assessment Report by the Intergovernmental Panel on Climate Change , global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the 20th,[5] which will increase sea level over the coming century and longer periods.[6][7] Increasing temperatures result in sea level rise by the thermal expansion Thermal expansion is the tendency of matter to change in volume in response to a change in temperature. When a substance is heated, its particles begin moving and become active thus maintaining a greater average separation. Materials which contract with increasing temperature are rare; this effect is limited in size, and only occurs within limited of water and through the addition of water to the oceans from the melting of mountain glaciers A glacier is a perennial mass of ice which moves over land. A glacier forms in locations where the mass accumulation of snow and ice exceeds ablation over many years. The word glacier comes from French via the Vulgar Latin glacia, and ultimately from Latin glacies meaning ice. The corresponding area of study is called glaciology, ice caps An ice cap is an ice mass that covers less than 50 000 km² of land area . Masses of ice covering more than 50 000 km² are termed an ice sheet and ice sheets An ice sheet is a mass of glacier ice that covers surrounding terrain and is greater than 50,000 km² , thus also known as continental glacier. The only current ice sheets are in Antarctica and Greenland; during the last glacial period at Last Glacial Maximum (LGM) the Laurentide ice sheet covered much of Canada and North America, the Weichselian. At the end of the 20th century, thermal expansion and melting of land ice contributed roughly equally to sea level rise, while thermal expansion is expected to contribute more than half of the rise in the upcoming century.[8] Values for predicted sea level rise over the course of this century typically range from 90 to 880 mm, with a central value of 480 mm. Models of glacier A glacier is a perennial mass of ice which moves over land. A glacier forms in locations where the mass accumulation of snow and ice exceeds ablation over many years. The word glacier comes from French via the Vulgar Latin glacia, and ultimately from Latin glacies meaning ice. The corresponding area of study is called glaciology mass balance (the difference between melting and accumulation of snow and ice on a glacier) give a theoretical maximum value for sea level rise in the current century of 2 metres The metre , symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole, its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it is defined as the distance travelled by light in a (and a "more plausible" one of 0.8 metres), based on limitations on how quickly glaciers can melt.[9]

Contents

Overview of sea-level change

Local and eustatic sea level

Water cycles between ocean An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (~3.61 X 1014 m2) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas, atmosphere The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night. Dry air contains roughly (by volume) 78% nitrogen, 21%, and glaciers A glacier is a perennial mass of ice which moves over land. A glacier forms in locations where the mass accumulation of snow and ice exceeds ablation over many years. The word glacier comes from French via the Vulgar Latin glacia, and ultimately from Latin glacies meaning ice. The corresponding area of study is called glaciology.

Local mean sea level (LMSL) is defined as the height of the sea with respect to a land benchmark, averaged over a period of time (such as a month or a year) long enough that fluctuations caused by waves In fluid dynamics, wind waves or, more precisely, wind-generated waves are surface waves that occur on the free surface of oceans, seas, lakes, rivers, and canals or even on small puddles and ponds. They usually result from the wind blowing over a vast enough stretch of fluid surface. Some waves in the oceans can travel thousands of miles before and tides Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and the rotation of the Earth. The tides occur with a period of approximately 12 hours and 25 minutes, and with an amplitude that is influenced by the alignment of the sun and moon and the shape of the near-shore are smoothed out. One must adjust perceived changes in LMSL to account for vertical movements of the land, which can be of the same order (mm/yr) as sea level changes. Some land movements occur because of isostatic Isostasy is a term used in geology to refer to the state of gravitational equilibrium between the earth's lithosphere and asthenosphere such that the tectonic plates "float" at an elevation which depends on their thickness and density. This concept is invoked to explain how different topographic heights can exist at the Earth's surface adjustment of the mantle The mantle is a part of a terrestrial planet or other rocky body large enough to have differentiated by density. The interior of the Earth, similar to the other terrestrial planets, is chemically divided into layers. The mantle is a highly viscous layer between the crust and the outer core. Earth's mantle is a rocky shell about 2,890 km thick that to the melting of ice sheets An ice sheet is a mass of glacier ice that covers surrounding terrain and is greater than 50,000 km² , thus also known as continental glacier. The only current ice sheets are in Antarctica and Greenland; during the last glacial period at Last Glacial Maximum (LGM) the Laurentide ice sheet covered much of Canada and North America, the Weichselian at the end of the last ice age. The weight of the ice sheet depresses the underlying land, and when the ice melts away the land slowly rebounds Post-glacial rebound is the rise of land masses that were depressed by the huge weight of ice sheets during the last glacial period, through a process known as isostatic depression. It affects northern Europe (especially Scotland, Fennoscandia and northern Denmark), Siberia, Canada, and the Great Lakes of Canada and the United States. Atmospheric pressure Atmospheric pressure is the force per unit area exerted against a surface by the weight of air above that surface in the Earth's atmosphere. In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. Low pressure areas have less atmospheric mass above, ocean currents An ocean current is a continuous, directed movement of ocean water generated by the forces acting upon this mean flow, such as breaking waves, wind, Coriolis force, temperature and salinity differences and tides caused by the gravitational pull of the Moon and the Sun. Depth contours, shoreline configurations and interaction with other currents and local ocean temperature Historically, two equivalent concepts of temperature have developed, the thermodynamic description and a microscopic explanation based on statistical physics. Since thermodynamics deals entirely with macroscopic measurements, the thermodynamic definition of temperature, first stated by Lord Kelvin, is stated entirely in empirical, measurable changes also can affect LMSL.

“Eustatic To an operator of a tide gauge, MSL means the "still water level"—the level of the sea with motions such as wind waves averaged out—averaged over a period of time such that changes in sea level, e.g., due to the tides, also get averaged out. One measures the values of MSL in respect to the land. Hence a change in MSL can result from” change (as opposed to local change) results in an alteration to the global sea levels, such as changes in the volume of water in the world oceans or changes in the volume of an ocean basin Hydrologically, an oceanic basin may be anywhere on Earth that is covered by seawater, but geologically ocean basins are large geologic basins that are below sea level. Geologically, there are other undersea geomorphological features such as the continental shelves, the deep ocean trenches, and the undersea mountain ranges which are not considered.

Short term and periodic changes

There are many factors which can produce short-term (a few minutes to 18.6 years) changes in sea level.

Short-term (periodic) causes Time scale (P = period) Vertical effect
Periodic sea level changes
Diurnal and semidiurnal astronomical tides 12–24 h P 0.2–10+ m
Long-period tides
Rotational variations (Chandler wobble The Chandler wobble is a small motion in the Earth's axis of rotation relative to the Earth's surface, which was discovered by American astronomer Seth Carlo Chandler in 1891. It amounts to 20 feet on the Earth's surface and has a period of 433 days. This wobble combines with another wobble with a period of one year so that the total polar motion) 14 month P
Lunar Node astronomical tides 18.613 year
Meteorological and oceanographic fluctuations
Atmospheric pressure Hours to months −0.7 to 1.3 m
Winds (storm surges Storm surge is an offshore rise of water associated with a low pressure weather system, typically a tropical cyclone. Storm surge is caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up higher than the ordinary sea level. Low pressure at the center of a weather system also has a small secondary effect,) 1–5 days Up to 5 m
Evaporation Evaporation is a type of vaporization of a liquid, that occurs only on the surface of a liquid. The other type of vaporization is boiling, that instead occurs on the entire mass of the liquid. Evaporation is also part of the water cycle and precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that is pulled down by gravity and deposited on the Earth's surface. The main forms of precipitation include rain, snow, ice pellets, and graupel. It occurs when the atmosphere, a large gaseous solution, becomes saturated with water vapour and the water (may also follow long-term pattern) Days to weeks
Ocean surface topography Topography is the study of Earth's surface shape and features or those of planets, moons, and asteroids. It is also the description of such surface shapes and features (especially their depiction in maps) (changes in water density The density of a material is defined as its mass per unit volume. The symbol of density is ρ . In some countries (for instance, in the United States), density is also defined as its weight per unit volume and currents) Days to weeks Up to 1 m
El Niño El Niño-Southern Oscillation,' often called simply ENSO, is a climate pattern that occurs across the tropical Pacific Ocean on average every five years, but over a period which varies from three to seven years, and is therefore, widely and significantly, known as "quasi-periodic." ENSO is best-known for its association with floods,/southern oscillation El Niño-Southern Oscillation, often called simply ENSO, is a climate pattern that occurs across the tropical Pacific Ocean on average every five years, but over a period which varies from three to seven years, and is therefore, widely and significantly, known as "quasi-periodic." ENSO is best-known for its association with floods, 6 mo every 5–10 yr Up to 0.6 m
Seasonal variations
Seasonal A season is a division of the year, marked by changes in weather, ecology, and hours of daylight water balance among oceans (Atlantic, Pacific, Indian)
Seasonal variations in slope of water surface
River A river is a natural watercourse, usually freshwater, flowing toward an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including stream, creek, brook, rivulet, and rill; there is no runoff/floods A flood is an overflow of an expanse of water that submerges land. The EU Floods directive defines a flood as a temporary covering by water of land not normally covered by water. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Flooding may result from the volume of water within a body of water, 2 months 1 m
Seasonal water density changes (temperature and salinity Salinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates. Salinity in Australian English and North American English may also refer to the salt content of soil) 6 months 0.2 m
Seiches
Seiches A seiche is a standing wave in an enclosed or partially enclosed body of water. Seiches and seiche-related phenomena have been observed on lakes, reservoirs, swimming pools, bays, and seas. The key requirement for formation of a seiche is that the body of water be at least partially bounded, allowing the formation of the standing wave (standing waves) Minutes to hours Up to 2 m
Earthquakes An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes are measured with a seismometer; a device which also records is known as a seismograph. The moment magnitude (or the related and mostly obsolete Richter magnitude) of an earthquake is conventionally reported, with magnitude 3 or
Tsunamis A tsunami (Japanese: 津波 [tsɯnami], lit. 'harbor wave'; English pronunciation: /suːˈnɑːmi/ (t)soo-NAH-mee) or tidal wave is a series of water waves (called a tsunami wave train) caused by the displacement of a large volume of a body of water, usually an ocean, but can occur in large lakes. Tsunamis are a frequent occurrence in Japan; (generate catastrophic long-period waves) Hours Up to 10 m
Abrupt change in land level Minutes Up to 10 m

Longer term changes

Various factors affect the volume or mass of the ocean, leading to long-term changes in eustatic sea level. The two primary influences are temperature (because the density of water Water is a chemical substance with the chemical formula H2O. Its molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state, water vapor or steam depends on temperature), and the mass In physics, mass commonly refers to any of three properties of matter, which have been shown experimentally to be equivalent: Inertial mass, active gravitational mass and passive gravitational mass. In everyday usage, mass is often taken to mean weight, but in scientific use, they refer to different properties of water locked up on land and sea as fresh water Freshwater or fresh water is naturally occurring water on the Earth's surface in bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Freshwater is characterized by having low concentrations of dissolved salts and other total dissolved solids. The term specifically excludes seawater and in rivers, lakes A lake is a terrain feature , a body of liquid on the surface of a world that is localized to the bottom of basin (another type of landform or terrain feature; that is not global). Another definition is a body of fresh or salt water of considerable size that is surrounded by land. On Earth a body of water is considered a lake when it is inland,, glaciers, polar ice caps A polar ice cap is a high latitude region of a planet or natural satellite that is covered in ice. There are no requirements with respect to size or composition for a body of ice to be termed a polar ice cap, nor any geological requirement for it to be over land; only that it must be a body of solid phase matter in the polar region. This causes, and sea ice Sea ice is largely formed from seawater that freezes. Because the oceans consist of salt water, this occurs below the freezing point of pure water, at about -1.8 °C. Over much longer geological timescales The geologic time scale is a chronologic schema relating stratigraphy to time that is used by geologists, paleontologists and other earth scientists to describe the timing and relationships between events that have occurred during the history of the Earth. The table of geologic time spans presented here agrees with the dates and nomenclature, changes in the shape of the oceanic basins and in land/sea distribution will affect sea level.

Observational and modelling studies of mass loss from glaciers and ice caps The retreat of glaciers since 1850 affects the availability of fresh water for irrigation and domestic use, mountain recreation, animals and plants that depend on glacier-melt, and in the longer term, the level of the oceans. Studied by glaciologists, the temporal coincidence of glacier retreat with the measured increase of atmospheric greenhouse indicate a contribution to sea-level rise of 0.2 to 0.4 mm/yr averaged over the 20th century.

Glaciers and ice caps

Each year about 8 mm (0.3 inch) of water from the entire surface of the oceans falls into the Antarctica and Greenland Greenland, the largest island in the world, is located between the Arctic Ocean and the North Atlantic Ocean, northeast of Canada and northwest of Iceland. Greenland has no land boundaries and 44,087 km of coastline. A sparse population is confined to small settlements along the coast. Greenland possesses the world's second largest ice sheet ice sheets as snowfall Snow is a type of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by external pressure. Snowflakes come in a variety of. If no ice returned to the oceans, sea level would drop 8 mm every year. To a first approximation, the same amount of water appeared to return to the ocean in icebergs An iceberg is a large piece of ice from freshwater that has broken off from a snow-formed glacier or ice shelf and is floating in open water. It may subsequently become frozen into pack ice. Alternatively, it may come to rest on the seabed in shallower water, causing ice scour or becoming an ice island and from ice melting at the edges. Scientists previously had estimated which is greater, ice going in or coming out, called the mass balance Crucial to the survival of a glacier is its mass balance, the difference between accumulation and ablation . Climate change may cause variations in both temperature and snowfall, causing changes in mass balance. Changes in mass balance control a glacier's long term behavior and is the most sensitive climate indicator on a glacier. From 1980-2008, important because it causes changes in global sea level. High-precision gravimetry Gravimetry is the measurement of the strength of a gravitational field. Gravimetry may be used when either the magnitude of gravitational field or the properties of matter responsible for its creation are of interest. The term gravimetry or gravimetric is also used in chemistry to define a class of analytical procedures, called gravimetric from satellites The Gravity Recovery And Climate Experiment , a joint mission of NASA and the German Space Agency, has been making detailed measurements of Earth's gravity field since its launch in March 2002 in low-noise flight has since determined Greenland is losing millions of tons per year, in accordance with loss estimates from ground measurement.[citation needed] Some estimates[which?] range up to 240 km3 per year in recent years.[10]

Ice shelves float on the surface of the sea and, if they melt, to first order they do not change sea level. Likewise, the melting of the northern polar ice cap which is composed of floating pack ice would not significantly contribute to rising sea levels. Because they are fresh, however, their melting would cause a very small increase in sea levels, so small that it is generally neglected. It can however be argued that if ice shelves melt it is a precursor to the melting of ice sheets on Greenland and Antarctica[citation needed].

The current rise in sea level observed from tide gauges, of about 1.8 mm/yr, is within the estimate range from the combination of factors above[13] but active research continues in this field. The terrestrial storage term, thought to be highly uncertain, is no longer positive, and shown to be quite large.

Since 1992 a number of satellites have been recording the change in sea level;[14][15] they display an acceleration in the rate of sea level change, but they have not been operating for long enough to work out whether this is a real signal, or just an artefact of short-term variation.

Past changes in sea level

Changes in sea level during the last 9,000 years

The sedimentary record

For generations, geologists have been trying to explain the obvious cyclicity of sedimentary deposits observed everywhere we look. The prevailing theories hold that this cyclicity primarily represents the response of depositional processes to the rise and fall of sea level. In the rock record, geologists see times when sea level was astoundingly low alternating with times when sea level was much higher than today, and these anomalies often appear worldwide. For instance, during the depths of the last ice age 18,000 years ago when hundreds of thousands of cubic miles of ice were stacked up on the continents as glaciers, sea level was 120 m (390 ft) lower, locations that today support coral reefs were left high and dry, and coastlines were miles farther basinward from the present-day coastline. It was during this time of very low sea level that there was a dry land connection between Asia and Alaska over which humans are believed to have migrated to North America (see Bering Land Bridge).

However, for the past 6,000 years (many centuries before the first known written records), the world's sea level has been gradually approaching the level we see today. During the previous interglacial about 120,000 years ago, sea level was for a short time about 6 m higher than today, as evidenced by wave-cut notches along cliffs in the Bahamas. There are also Pleistocene coral reefs left stranded about 3 metres above today's sea level along the southwestern coastline of West Caicos Island in the West Indies. These once-submerged reefs and nearby paleo-beach deposits are silent testimony that sea level spent enough time at that higher level to allow the reefs to grow (exactly where this extra sea water came from—Antarctica or Greenland—has not yet been determined). Similar evidence of geologically recent sea level positions is abundant around the world.

Estimates

See IPCC TAR, figure 11.4 for a graph of sea level changes over the past 140,000 years.[16]

U. S. Tide Gauge Measurements

U. S. Sea Level Trends 1900-2003

Tide gauges in the United States show considerable variation because some land areas are rising and some are sinking. For example, over the past 100 years, the rate of sea level rise varies from about an increase of 0.36 inches (9.1 mm) per year along the Louisiana Coast (due to land sinking), to a drop of a few inches per decade in parts of Alaska (due to post-glacial rebound). The rate of sea level rise increased during the 1993-2003 period compared with the longer-term average (1961–2003), although it is unclear whether the faster rate reflects a short-term variation or an increase in the long-term trend.[19]

Amsterdam Sea Level Measurements

The longest running sea-level measurements are recorded at Amsterdam, in the Netherlands—part of which (about 25%) lies beneath sea level. Records from 1700 onwards can be found at http://www.pol.ac.uk/psmsl/longrecords/longrecords.html. Since 1850, a rise of approx 1.5 mm/year is shown here.

Australian Sea Level Change

The London Royal Society calculates net sea level rise in Australia at 1 mm/yr[20]—an important result for the Southern Hemisphere. The National Tidal Center also graphs 32 gauges, some since 1880, for the entire coastline[21]

Future sea level rise

In 2007, the Intergovernmental Panel on Climate Change's Fourth Assessment Report (AR4) predicted that by 2100, global warming will lead to a sea level rise of 180 to 590 mm[22], depending on which of six possible world scenarios comes to pass, and barring rapid dynamical changes in ice flow.[23] More recent research, which has observed rapid declines in ice mass balance from both Greenland and Antarctica, finds that sea-level rise by 2100 is likely to be at least twice as large as that presented by IPCC AR4, with an upper limit of about two meters.[24]

These sea level rises could lead to potentially catastrophic difficulties for shore-based communities in the next centuries: for example, many major cities such as London and New Orleans already need storm-surge defenses, and would need more if sea level rose, though they also face issues such as sinking land.[25] Sea level rise could also displace many shore-based populations: for example it is estimated that a sea level rise of just 200 mm could create 740,000 homeless people in Nigeria.[26] Maldives, Tuvalu, and other low-lying countries are among the areas that are at the highest level of risk. The UN's environmental panel has warned that, at current rates, sea level would be high enough to make the Maldives uninhabitable by 2100.[27][28]

Future sea level rise, like the recent rise, is not expected to be globally uniform (details below). Some regions show a sea-level rise substantially more than the global average (in many cases of more than twice the average), and others a sea level fall.[29] However, models disagree as to the likely pattern of sea level change.[30]

In September 2008, the Delta Commission presided by Dutch politician Cees Veerman advised in a report that The Netherlands would need a massive new building program to strengthen the country's water defenses against the anticipated effects of global warming for the next 190 years. This commission was created in September 2007, after the damage caused by Hurricane Katrina prompted reflection and preparations. Those included drawing up worst-case plans for evacuations. The plan included more than €100 billion, or $144 billion, in new spending through the year 2100 to take measures, such as broadening coastal dunes and strengthening sea and river dikes.

The commission said the country must plan for a rise in the North Sea of around 30 inches, or 80 centimeters, by 2100 and of as much as 4.25 feet, or 1.3 meters, by 2100, and 6.5–13 feet by 2200.[31]

Main article: Delta Works

Intergovernmental Panel on Climate Change results

The results from the IPCC Third Assessment Report (TAR) sea level chapter (convening authors John A. Church and Jonathan M. Gregory) are given below.

IPCC change factors 1990-2100 IS92a prediction SRES prediction
Thermal expansion 110 to 430 mm
Glaciers 10 to 230 mm[32] (or 50 to 110 mm)[33]
Greenland ice –20 to 90 mm
Antarctic ice –170 to 20 mm
Terrestrial storage –83 to 30 mm
Ongoing contributions from ice sheets in response to past climate change 0 to 55 mm
Thawing of permafrost 0 to 5 mm
Deposition of sediment not specified
Total global-average sea level rise (IPCC result, not sum of above)[32] 110 to 770 mm 90 to 880 mm (central value of 480 mm)

The sum of these components indicates a rate of eustatic sea level rise (corresponding to a change in ocean volume) from 1910 to 1990 ranging from –0.8 to 2.2 mm/yr, with a central value of 0.7 mm/yr. The upper bound is close to the observational upper bound (2.0 mm/yr), but the central value is less than the observational lower bound (1.0 mm/yr), i.e., the sum of components is biased low compared to the observational estimates. The sum of components indicates an acceleration of only 0.2 (mm/yr)/century, with a range from –1.1 to +0.7 (mm/yr)/century, consistent with observational finding of no acceleration in sea level rise during the 20th century. The estimated rate of sea-level rise from anthropogenic climate change from 1910 to 1990 (from modeling studies of thermal expansion, glaciers and ice sheets) ranges from 0.3 to 0.8 mm/yr. It is very likely that 20th century warming has contributed significantly to the observed sea-level rise, through thermal expansion of sea water and widespread loss of land ice.[32]

A common perception is that the rate of sea-level rise should have accelerated during the latter half of the 20th century, but tide gauge data for the 20th century show no significant acceleration. Estimates obtained are based on AOGCMs for the terms directly related to anthropogenic climate change in the 20th century, i.e., thermal expansion, ice sheets, glaciers and ice caps... The total computed rise indicates an acceleration of only 0.2 (mm/yr)/century, with a range from -1.1 to +0.7 (mm/yr)/century, consistent with observational finding of no acceleration in sea-level rise during the 20th century.[34] The sum of terms not related to recent climate change is -1.1 to +0.9 mm/yr (i.e., excluding thermal expansion, glaciers and ice caps, and changes in the ice sheets due to 20th century climate change). This range is less than the observational lower bound of sea level rise. Hence it is very likely that these terms alone are an insufficient explanation, implying that 20th century climate change has made a contribution to 20th century sea level rise.[13] Recent figures of human, terrestrial impoundment came too late for the 3rd Report, and would revise levels upward for much of the 20th century.

Uncertainties and criticisms regarding IPCC results

Glacier contribution

It is well known that glaciers are subject to surges in their rate of movement with consequent melting when they reach lower altitudes and/or the sea. The contributors to Annals of Glaciology [2], Volume 36 [3] (2003) discussed this phenomenon extensively and it appears that slow advance and rapid retreat have persisted throughout the mid to late Holocene in nearly all of Alaska's glaciers. Historical reports of surge occurrences in Iceland's glaciers go back several centuries. Thus rapid retreat can have several other causes than CO2 increase in the atmosphere.

The results from Dyurgerov show a sharp increase in the contribution of mountain and subpolar glaciers to sea level rise since 1996 (0.5 mm/yr) to 1998 (2 mm/yr) with an average of approx. 0.35 mm/yr since 1960.[35]

Of interest also is Arendt et al.,[36] who estimate the contribution of Alaskan glaciers of 0.14±0.04 mm/yr between the mid 1950s to the mid 1990s increasing to 0.27 mm/yr in the middle and late 1990s.

Greenland contribution

Krabill et al.[37] estimate a net contribution from Greenland to be at least 0.13 mm/yr in the 1990s. Joughin et al.[38] have measured a doubling of the speed of Jakobshavn Isbræ between 1997 and 2003. This is Greenland's largest outlet glacier; it drains 6.5% of the ice sheet, and is thought to be responsible for increasing the rate of sea level rise by about 0.06 millimetres per year, or roughly 4% of the 20th century rate of sea level increase.[39] In 2004, Rignot et al.[40] estimated a contribution of 0.04±0.01 mm/yr to sea level rise from southeast Greenland.

Rignot and Kanagaratnam[41] produced a comprehensive study and map of the outlet glaciers and basins of Greenland. They found widespread glacial acceleration below 66 N in 1996 which spread to 70 N by 2005; and that the ice sheet loss rate in that decade increased from 90 to 200 cubic km/yr; this corresponds to an extra 0.25 to 0.55 mm/yr of sea level rise.

In July 2005 it was reported[42] that the Kangerdlugssuaq glacier, on Greenland's east coast, was moving towards the sea three times faster than a decade earlier. Kangerdlugssuaq is around 1,000 m thick, 7.2 km (4.5 miles) wide, and drains about 4% of the ice from the Greenland ice sheet. Measurements of Kangerdlugssuaq in 1988 and 1996 showed it moving at between 5 and 6 km/yr (3.1 to 3.7 miles/yr) (in 2005 it was moving at 14 km/yr [8.7 miles/yr]).

According to the 2004 Arctic Climate Impact Assessment, climate models project that local warming in Greenland will exceed 3° Celsius during this century. Also, ice sheet models project that such a warming would initiate the long-term melting of the ice sheet, leading to a complete melting of the Greenland ice sheet over several millennia, resulting in a global sea level rise of about seven metres.[43]

Antarctic contribution

See also: Antarctica#Ice mass and global sea level

On the Antarctic continent itself, the large volume of ice present stores around 70 % of the world's fresh water.[44] This ice sheet is constantly gaining ice from snowfall and losing ice through outflow to the sea. West Antarctica is currently experiencing a net outflow of glacial ice, which will increase global sea level over time. A review of the scientific studies looking at data from 1992 to 2006 suggested a net loss of around 50 Gigatonnes of ice per year was a reasonable estimate (around 0.14 mm of sea level rise),[45] although significant acceleration of outflow glaciers in the Amundsen Sea Embayment could have more than doubled this figure for the year 2006.[46]

East Antarctica is a cold region with a ground base above sea level and occupies most of the continent. This area is dominated by small accumulations of snowfall which becomes ice and thus eventually seaward glacial flows. The mass balance of the East Antarctic Ice Sheet as a whole is thought to be slightly positive (lowering sea level) or near to balance.[45][46] However, increased ice outflow has been suggested in some regions.[46][47]

Effects of snowline and permafrost

The snowline altitude is the altitude of the lowest elevation interval in which minimum annual snow cover exceeds 50%. This ranges from about 5,500 metres above sea-level at the equator down to sea-level at about 65° N&S latitude, depending on regional temperature amelioration effects. Permafrost then appears at sea-level and extends deeper below sea-level pole-wards. The depth of permafrost and the height of the ice-fields in both Greenland and Antarctica means that they are largely invulnerable to rapid melting. Greenland Summit is at 3,200 metres, where the average annual temperature is minus 32 °C. So even a projected 4 °C rise in temperature leaves it well below the melting point of ice. Frozen Ground 28, December 2004, has a very significant map of permafrost affected areas in the Arctic. The continuous permafrost zone includes all of Greenland, the North of Labrador, NW Territories, Alaska north of Fairbanks, and most of NE Siberia north of Mongolia and Kamchatka. Continental ice above permafrost is very unlikely to melt quickly. As most of the Greenland and Antarctic ice sheets lie above the snowline and/or base of the permafrost zone, they cannot melt in a timeframe much less than several millennia; therefore they are unlikely to contribute significantly to sea-level rise in the coming century.

Polar ice

The sea level will rise above its current level if more polar ice melts. However, compared to the heights of the ice ages, today there are very few continental ice sheets remaining to be melted. It is estimated that Antarctica, if fully melted, would contribute more than 60 metres of sea level rise, and Greenland would contribute more than 7 metres. Small glaciers and ice caps on the margins of Greenland and the Antarctic Peninsula might contribute about 0.5 metres. While the latter figure is much smaller than for Antarctica or Greenland it could occur relatively quickly (within the coming century) whereas melting of Greenland would be slow (perhaps 1,500 years to fully deglaciate at the fastest likely rate) and Antarctica even slower.[11] However, this calculation does not account for the possibility that as meltwater flows under and lubricates the larger ice sheets, they could begin to move much more rapidly towards the sea.[48][49]

In 2002, Rignot and Thomas[50] found that the West Antarctic and Greenland ice sheets were losing mass, while the East Antarctic ice sheet was probably in balance (although they could not determine the sign of the mass balance for The East Antarctic ice sheet). Kwok and Comiso (J. Climate, v15, 487-501, 2002) also discovered that temperature and pressure anomalies around West Antarctica and on the other side of the Antarctic Peninsula correlate with recent Southern Oscillation events.

In 2004 Rignot et al.[40] estimated a contribution of 0.04±0.01 mm/yr to sea level rise from South East Greenland. In the same year, Thomas et al.[51] found evidence of an accelerated contribution to sea level rise from West Antarctica. The data showed that the Amundsen Sea sector of the West Antarctic Ice Sheet was discharging 250 cubic kilometres of ice every year, which was 60% more than precipitation accumulation in the catchment areas. This alone was sufficient to raise sea level at 0.24 mm/yr. Further, thinning rates for the glaciers studied in 2002-2003 had increased over the values measured in the early 1990s. The bedrock underlying the glaciers was found to be hundreds of metres deeper than previously known, indicating exit routes for ice from further inland in the Byrd Subpolar Basin. Thus the West Antarctic ice sheet may not be as stable as has been supposed.

In 2005 it was reported that during 1992-2003, East Antarctica thickened at an average rate of about 18 mm/yr while West Antarctica showed an overall thinning of 9 mm/yr. associated with increased precipitation. A gain of this magnitude is enough to slow sea-level rise by 0.12±0.02 mm/yr.[52]

Effects of sea level rise

Based on the projected increases stated above, the IPCC TAR WG II report notes that current and future climate change would be expected to have a number of impacts, particularly on coastal systems.[53] Such impacts may include increased coastal erosion, higher storm-surge flooding, inhibition of primary production processes, more extensive coastal inundation, changes in surface water quality and groundwater characteristics, increased loss of property and coastal habitats, increased flood risk and potential loss of life, loss of nonmonetary cultural resources and values, impacts on agriculture and aquaculture through decline in soil and water quality, and loss of tourism, recreation, and transportation functions.

There is an implication that many of these impacts will be detrimental—especially for the three-quarters of the world's poor who depend on agriculture systems.[54] The report does, however, note that owing to the great diversity of coastal environments; regional and local differences in projected relative sea level and climate changes; and differences in the resilience and adaptive capacity of ecosystems, sectors, and countries, the impacts will be highly variable in time and space.

Statistical data on the human impact of sea level rise is scarce. A study in the April, 2007 issue of Environment and Urbanization reports that 634 million people live in coastal areas within 30 feet (9.1 m) of sea level. The study also reported that about two thirds of the world's cities with over five million people are located in these low-lying coastal areas. The IPCC report of 2007 estimated that accelerated melting of the Himalayan ice caps and the resulting rise in sea levels would likely increase the severity of flooding in the short-term during the rainy season and greatly magnify the impact of tidal storm surges during the cyclone season. A sea-level rise of just 400 mm in the Bay of Bengal would put 11 percent of the Bangladesh's coastal land underwater, creating 7 to 10 million climate refugees.

Island nations

IPCC assessments suggest that deltas and small island states are particularly vulnerable to sea level rise caused by both thermal expansion and ocean volume. Relative sea level rise (mostly caused by subsidence) is currently causing substantial loss of lands in some deltas.[55] Sea level changes have not yet been conclusively proven to have directly resulted in environmental, humanitarian, or economic losses to small island states, but the IPCC and other bodies have found this a serious risk scenario in coming decades.[56]

Many media reports have focused the island nations of the Pacific, notably the Polynesian islands of Tuvalu, which based on more severe flooding events in recent years, was thought to be "sinking" due to sea level rise.[57] A scientific review in 2000 reported that based on University of Hawaii gauge data, Tuvalu had experienced a negligible increase in sea-level of 0.07 mm a year over the past two decades, and that ENSO had been a larger factor in Tuvalu's higher tides in recent years.[58] A subsequent study by John Hunter from the University of Tasmania, however, adjusted for ENSO effects and the movement of the gauge (which was thought to be sinking). Hunter concluded that Tuvalu had been experiencing sea-level rise of about 1.2 mm per year.[58][59] The recent more frequent flooding in Tuvalu may also be due to an erosional loss of land during and following the actions of 1997 cyclones Gavin, Hina, and Keli.[60]

Reuters has reported other Pacific islands are facing a severe risk including Tegua island in Vanuatu. Claims that Vanuatu data shows no net sea level rise, are not substantiated by tide gauge data.[citation needed] Vanuatu tide gauge data show a net rise of ~50 mm from 1994-2004.[citation needed] Linear regression of this short time series suggests a rate of rise of ~7 mm/y[citation needed], though there is considerable variability and the exact threat to the islands is difficult to assess using such a short time series.

Numerous options have been proposed that would assist island nations to adapt to rising sea level.[61]

Satellite sea level measurement

Satellite Measurement of Sea Level. 1993-2010 Sea level trends from satellite altimetry.

Sea level rise estimates from satellite altimetry are 3.1 ± 0.4 mm/yr for 1993-2003 (Leuliette et al. (2004)). This exceeds those from tide gauges. It is unclear whether this represents an increase over the last decades; variability; true differences between satellites and tide gauges; or problems with satellite calibration.[34] Knowing the current altitude of a satellite which can measure sea level to a precision of about 20 millimetres (e.g. the Topex/Poseidon system) is primarily complicated by orbital decay and the difference between the assumed orbit and the earth geoid [62]. This problem is partially corrected by regular re-calibration of satellite altimeters from land stations whose height from MSL is known by surveying. Over water, the height is calibrated from tide gauge data which is needed to correct for tides and atmospheric effects on sea level.

See also

energy portal

Notes

  1. ^ Bruce C. Douglas (1997). "Global Sea Rise: A Redetermination". Surveys in Geophysics 18: 279–292. doi:10.1023/A:1006544227856.
  2. ^ a b Church, John; White, Neil (January 6, 2006). "A 20th century acceleration in global sea-level rise". Geophysical Research Letters 33: L01602. doi:10.1029/2005GL024826. L01602. http://www.agu.org/pubs/crossref/2006/2005GL024826.shtml. Retrieved 2010-05-17 pdf is here
  3. ^ Chambers, D. P.; Ries, J. C.; Urban, T. J. (2003). "Calibration and Verification of Jason-1 Using Global Along-Track Residuals with TOPEX". Marine Geodesy 26: 305. doi:10.1080/714044523.
  4. ^ Bindoff, NL et al.. "Observations: Oceanic Climate Change and Sea Level". Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press. http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter5.pdf.
  5. ^ Nathaniel L. Bindoff, Jürgen Willebrand et al. (2007). "Observations: Oceanic Climate Change and Sea Level". in Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom and New York, NY, USA.: Cambridge University Press. http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter5.pdf.
  6. ^ Meehl, G.A., T.F. Stocker, W.D. Collins, P. Friedlingstein, A.T. Gaye, J.M. Gregory, A. Kitoh, R. Knutti, J.M. Murphy, A. Noda, S.C.B. Raper,, I.G. Watterson, A.J. Weaver and Z.-C. Zhao, 2007: Global Climate Projections. In: Climate, Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S.,D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Projections of Global Average Sea Level Change for the 21st Century Chapter 10, p 820
  7. ^ http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter10.pdf
  8. ^ "IPCC AR4 Chapter 5". IPCC. 2007. pp. 409. http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter5.pdf. Retrieved 13 February 2010.
  9. ^ Pfeffer, Wt; Harper, Jt; O'Neel, S (Sep 2008). "Kinematic constraints on glacier contributions to 21st-century sea-level rise.". Science (New York, N.Y.) 321 (5894): 1340–3. doi:10.1126/science.1159099. ISSN 0036-8075. PMID 18772435.
  10. ^ Yale Environment 360, quoting Danish Meteorological Institute
  11. ^ a b "Some physical characteristics of ice on Earth". Climate Change 2001: The Scientific Basis. http://www.grida.no/climate/ipcc_tar/wg1/412.htm#tab113.
  12. ^ Geologic Contral on Fast Ice Flow - West Antarctic Ice Sheet
  13. ^ a b "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/428.htm. Retrieved 2005-12-19.
  14. ^ "Ocean Surface Topography from Space". NASA/JPL. http://topex-www.jpl.nasa.gov/mission/topex.html.
  15. ^ "Ocean Surface Topography from Space". NASA/JPL. http://sealevel.jpl.nasa.gov/mission/jason-1.html.
  16. ^ "IPCC TAR, figure 11.4". http://www.grida.no/climate/ipcc_tar/wg1/fig11-4.htm. Retrieved 2005-12-19.
  17. ^ Americas on alert for sea level rise
  18. ^ "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/422.htm#tab119. Retrieved 2005-12-19.
  19. ^ U. S. Environmental Protection Agency "Sea Level Changes"
  20. ^ LANDMARK STUDY CONFIRMS RISING AUSTRALIAN SEA LEVEL
  21. ^ Australian Mean Sea Level Survey 2003
  22. ^ Intergovernmental Panel on Climate Change (2007). "Coastal Systems and Low-lying Areas, Table 6.3" (pdf). Coastal Systems and Low-lying Areas. http://www.ipcc.ch/pdf/assessment-report/ar4/wg2/ar4-wg2-chapter6.pdf. Retrieved 2009-07-27.
  23. ^ Intergovernmental Panel on Climate Change (2007). "Projected global average surface warming and sea level rise at the end of the 21st century, Table SPM.3" (pdf). Projected global average surface warming and sea level rise at the end of the 21st century.. http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm.pdf. Retrieved 2009-12-22.
  24. ^ I. Allison, N.L. Bindoff, R.A. Bindschadler, P.M. Cox, N. de Noblet, M.H. England, J.E. Francis, N. Gruber, A.M. Haywood, D.J. Karoly, G. Kaser, C. Le Quéré, T.M. Lenton, M.E. Mann, B.I. McNeil, A.J. Pitman, S. Rahmstorf, E. Rignot, H.J. Schellnhuber, S.H. Schneider, S.C. Sherwood, R.C.J. Somerville, K. Steffen, E.J. Steig, M. Visbeck, A.J. Weaver (2009). "Copenhagen Diagnosis". The Copenhagen Diagnosis, 2009: Updating the World on the Latest Climate Science. http://www.copenhagendiagnosis.org/read/default.html. Retrieved 2009-12-22.
  25. ^ Church, J.A. and J.M. Gregory. "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/index.htm. Retrieved 2005-12-19.
  26. ^ Klaus Paehler. "Nigeria in the Dilemma of Climate Change". http://www.kas.de/proj/home/pub/33/2/dokument_id-11468/index.html. Retrieved 2008-11-04. ,
  27. ^ Megan Angelo (1 May 2009). "Honey, I Sunk the Maldives: Environmental changes could wipe out some of the world's most well-known travel destinations". http://travel.yahoo.com/p-interests-27384279;_ylc=X3oDMTFxcWIyczFpBF9TAzI3MTYxNDkEX3MDMjcxOTQ4MQRzZWMDZnAtdG9kYXltb2QEc2xrA21hbGRpdmVzLTQtMjgtMDk-.
  28. ^ Kristina Stefanova (19 April 2009). "Climate refugees in Pacific flee rising sea". http://www.washingtontimes.com/news/2009/apr/19/rising-sea-levels-in-pacific-create-wave-of-migran/.
  29. ^ "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/432.htm. Retrieved 2005-12-19.
  30. ^ "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/fig11-13.htm. Retrieved 2005-12-19.
  31. ^ "Dutch draw up drastic measures to defend coast against rising seas"
  32. ^ a b c "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/409.htm. Retrieved 2005-12-19.
  33. ^ "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/434.htm#11542. Retrieved 2005-12-19.
  34. ^ a b c "Climate Change 2001: The Scientific Basis". http://www.grida.no/climate/ipcc_tar/wg1/426.htm#fig1110. Retrieved 2005-12-19.
  35. ^ Dyurgerov, Mark. 2002. Glacier Mass Balance and Regime: Data of Measurements and Analysis. INSTAAR Occasional Paper No. 55, ed. M. Meier and R. Armstrong. Boulder, CO: Institute of Arctic and Alpine Research, University of Colorado. Distributed by National Snow and Ice Data Center, Boulder, CO. A shorter discussion is at [1]
  36. ^ Arendt, AA; et al. (July 2002). "Rapid Wastage of Alaska Glaciers and Their Contribution to Rising Sea Level". Science 297 (5580): 382–386. doi:10.1126/science.1072497. PMID 12130781.
  37. ^ Krabill, W; et al. (21 July 2000). "Greenland Ice Sheet: High-Elevation Balance and Peripheral Thinning". Science 289 (5478): 428–430. doi:10.1126/science.289.5478.428. PMID 10903198.
  38. ^ Joughin, I; et al. (December 2004). "Large fluctuations in speed on Greenland's Jakobshavn Isbræ glacier". Nature 432 (7017): 608–610. doi:10.1038/nature03130. PMID 15577906.
  39. ^ Report shows movement of glacier has doubled speed | SpaceRef - Your Space Reference
  40. ^ a b Rignot, E.; et al. (2004). "Rapid ice discharge from southeast Greenland glaciers". Geophysical Research Letters 31: L10401. doi:10.1029/2004GL019474.
  41. ^ Rignot, E; Kanagaratnam (2006). "Changes in the Velocity Structure of the Greenland Ice Sheet". Science 311 (5763): 986 et seq.. doi:10.1126/science.1121381. PMID 16484490. http://www.sciencemag.org/cgi/content/abstract/311/5763/986?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=luckman&searchid=1140284328766_4322&FIRSTINDEX=0&journalcode=sci.
  42. ^ Connor, Steve (2005-07-25). "Melting Greenland glacier may hasten rise in sea level". The Independent (London). http://news.independent.co.uk/world/environment/article301493.ece. Retrieved 2010-04-30.
  43. ^ http://www.metoffice.gov.uk/corporate/pressoffice/adcc/BookCh4Jan2006.pdf
  44. ^ "How Stuff Works: polar ice caps". howstuffworks.com. http://science.howstuffworks.com/question473.htm. Retrieved 2006-02-12.
  45. ^ a b Shepherd A., Wingham D, (2007). "Recent sea-level contributions of the Antarctic and Greenland Ice Sheets". Science 315 (5818): 1529–1532. doi:10.1126/science.1136776. PMID 17363663.
  46. ^ a b c Rignot E., Bamber J.L., van den Broeke, M.R., Davis C., Li Y., van de Berg W.J., van Meijgaard E. (2008). "Recent Antarctic ice mass loss from radar interferometry and regional climate modelling". Nature Geoscience 1: 106–110. doi:10.1038/ngeo102.
  47. ^ Chen, J.L., Wilson C.R., Tapley B.D., Blankenship D., Young D. (2007). "Antarctic regional ice loss rates from GRACE". Earth and Planetary Science Letters 266: 140–148. doi:10.1016/j.epsl.2007.10.057.
  48. ^ Zwally H.J. et al. (2002). "Surface Melt-Induced Acceleration of Greenland Ice-Sheet Flow". Science 297 (5579): 218–222. doi:10.1126/science.1072708. PMID 12052902. http://www.sciencemag.org/cgi/content/abstract/297/5579/218.
  49. ^ "Greenland Ice Sheet flows faster during summer melting". Goddard Space Flight Center (press release). 2006-06-02. http://www.gsfc.nasa.gov/topstory/20020606greenland.html.
  50. ^ Rignot, E; Thomas (2002). "Mass Balance of Polar Ice Sheets". Science 297 (5586): 1502–1506. doi:10.1126/science.1073888. PMID 12202817.
  51. ^ Thomas, R; et al. (2004). "Accelerated Sea-Level Rise from West Antarctica". Science 306 (5694): 255–258. doi:10.1126/science.1099650. PMID 15388895.
  52. ^ Davis, Curt H.; Yonghong Li, Joseph R. McConnell, Markus M. Frey, Edward Hanna (24 June 2005). "Snowfall-Driven Growth in East Antarctic Ice Sheet Mitigates Recent Sea-Level Rise". Science 308 (5730): 1898–1901. doi:10.1126/science.1110662. PMID 15905362.
  53. ^ "Climate Change 2001: Impacts, Adaptation and Vulnerability". http://www.grida.no/climate/ipcc_tar/wg2/292.htm. Retrieved 2005-12-19.
  54. ^ "Climate Shocks: Risk and Vulnerability in an Unequal World." Human Development report 2007/2008. hdr.undp.org/media/hdr_20072008_summary_english.pdf
  55. ^ Tidwell, Mike (2006). The Ravaging Tide: Strange Weather, Future Katrinas, and the Coming Death of America's Coastal Cities. Free Press. ISBN 0-7432-9470-X.
  56. ^ The Future Oceans - Warming Up, Rising High, Turning Sour
  57. ^ Levine, Mark (December 2002). "Tuvalu Toodle-oo". Outside Magazine. http://outside.away.com/outside/features/200212/200212_tuvalu_1.html. Retrieved 2005-12-19.
  58. ^ a b Patel, Samir S. (April 5, 2006). "A Sinking Feeling". Nature. http://www.nature.com/nature/journal/v440/n7085/full/440734a.html. Retrieved 2007-11-15.
  59. ^ Hunter, J.A. (August 12, 2002). "A Note on Relative Sea Level Rise at Funafuti, Tuvalu" (PDF). http://staff.acecrc.org.au/~johunter/tuvalu.pdf.
  60. ^ Field, Michael J. (December 2001). "Sea Levels Are Rising". Pacific Magazine. http://www.pacificislands.cc/pm122001/pmdefault.php?urlarticleid=0009. Retrieved 2005-12-19.
  61. ^ "Policy Implications of Sea Level Rise: The Case of the Maldives.". Proceedings of the Small Island States Conference on Sea Level Rise. November 14–18, 1989. Male, Republic of Maldives. Edited by Hussein Shihab. http://papers.risingsea.net/Maldives/Small_Island_States_3.html. Retrieved 2007-01-12.
  62. ^ http://ibis.grdl.noaa.gov/SAT/pubs/papers/2001_Cheney_Encycl.pdf

References

External links

This article's use of external links may not follow Wikipedia's policies or guidelines. Please improve this article by removing excessive and inappropriate external links or by converting links into footnote references. (September 2009)
Maps that show a Rise in Sea Levels
Physical oceanography - Waves and Currents
Waves Airy wave theory · Ballantine Scale · Boussinesq approximation · Breaking wave · Clapotis · Cnoidal wave · Cross sea · Dispersion · Infragravity waves · Edge wave · Equatorial waves · Fetch · Freak wave · Gravity wave · Internal gravity waves · Internal wave · Kelvin wave · Luke's variational principle · Mild-slope equation · Rogue wave · Rossby wave · Rossby-gravity waves · Sea state · Seiche · Significant wave height · Sneaker wave · Soliton · Stokes drift · Surf wave · Swells · Tsunami · Undertow · Ursell number · Wave base · Wave height · Wave power · Wave shoaling · Wave radar · Wave turbulence · Waves and shallow water · Shallow water equations · Wind wave · Wind wave model · More...
Circulation Atmospheric circulation · Baroclinity · Boundary current · Coriolis effect · Downwelling · Eddy · Ekman layer · Ekman spiral · Ekman transport · El Niño-Southern Oscillation · Geostrophic current · Gulf Stream · Halothermal circulation · Humboldt Current · Hydrothermal circulation · Global circulation model · Langmuir circulation · Longshore drift · Loop Current · Maelstrom · Ocean current · Ocean dynamics · Ocean gyre · Rip current · Thermohaline circulation · Shutdown of thermohaline circulation · Subsurface currents · Sverdrup balance · Whirlpool · Upwelling · GLODAP · MOM · WOCE · More...
Tides Amphidromic point · Earth tide · Head of tide · Internal tide · Lunitidal interval · Perigean spring tide · Rule of twelfths · Slack water · Spring/neap tide · Tidal bore · Tidal force · Tidal power · Tidal race · Tidal range · Tidal resonance · Tide · Tide gauge · Tideline · More...
Physical oceanography - Other
Landforms Abyssal fan · Abyssal plain · Atoll · Bathymetric chart · Cold seep · Continental margin · Continental rise · Continental shelf · Contourite · Hydrography · Guyot · Oceanic basin · Oceanic plateau · Oceanic trench · Passive margin · Seabed · Seamount · Submarine canyon · Coastal geography · More...
Plate tectonics Black smoker · Convergent boundary · Divergent boundary · Fracture zone · Hydrothermal vent · Marine geology · Mid-ocean ridge · Mohorovičić discontinuity · Morley–Vine–Matthews hypothesis · Oceanic crust · Outer trench swell · Ridge-push · Seafloor spreading · Slab window · Subduction · Transform fault · Volcanic arc · More...
Ocean zones Benthic · Deep ocean water · Deep sea · Littoral · Mesopelagic · Oceanic zone · Pelagic · Photic
Sea level Current sea level rise · Future sea level · Sea-level curve · DART · GLOSS · NOOS · OSTM · WGS
Acoustics Ocean acoustic tomography · Sofar bomb · SOFAR channel · Underwater acoustics · Hydroacoustics
Other Alvin · Argo · Benthic lander · Color of water · Marginal sea · Mooring · Ocean · Ocean energy · Ocean exploration · Ocean observations · Ocean pollution · Ocean reanalysis · Ocean surface topography · Ocean thermal energy conversion · Oceanography · Sea surface microlayer · Sea surface temperature · Seawater · Science On a Sphere · Thermocline · Underwater glider · Water column · World Ocean Atlas · NODC · More...
Global warming and climate change
Temperatures
Instrumental record · Satellite record · Past 1,000 years · Since 1880 · Geologic record · Historical climatology · Paleoclimatology
Causes
Anthropogenic Attribution of recent climate change · Aviation · Biofuel · Carbon dioxide · Earth's energy budget · Earth's radiation balance · Fossil fuel · Global dimming · Global warming potential · Greenhouse effect · Greenhouse gases · Land use and forestry · Radiative forcing · Urban heat island
Natural

Albedo · Bond events · Cloud forcing · Feedbacks · Glaciation · Global cooling · Ocean variability (AMO · ENSO · IOD · PDO) · Orbital variations · Orbital forcing · Solar variation · Volcanism
Models Global climate model
History
History of climate change science · Svante Arrhenius · Charles David Keeling
Opinion and controversy
Scientific opinion on climate change · Scientists opposing the mainstream assessment
Politics
Politics

United Nations Framework Convention on Climate Change (UNFCCC / FCCC) · Intergovernmental Panel on Climate Change (IPCC) · Climate change denial
Potential effects and issues
General Abrupt climate change · Climate change and agriculture · Drought · Economics of global warming · Fisheries and climate change · Glacier retreat · Mass extinction · Ozone depletion · Ocean acidification · Runaway climate change · Sea level rise · Season creep · Shutdown of thermohaline circulation
By country Australia · India · United States
Mitigation
Kyoto Protocol Clean Development Mechanism · Joint Implementation · Bali roadmap
Governmental European Climate Change Programme · United Kingdom Climate Change Programme · Coal phase out
Schemes Emissions trading · Personal carbon trading · Carbon tax · Carbon offset · Carbon credit · Carbon dioxide sink (carbon sequestration) · Cap and Share
Energy conservation Efficient energy use · Renewable energy · Renewable energy commercialization · Renewable energy development · Soft energy path
Other G8 Climate Change Roundtable · Individual and political action on climate change · Climate change mitigation scenarios
Proposed adaptations
Strategies Damming glacial lakes · Drought tolerance · Irrigation investment · Rainwater storage · Sustainable development · Weather control
Programmes Avoiding Dangerous Climate Change · Land Allocation Decision Support System
Category:Global warming · Category:Climate change · Glossary of climate change · Index of climate change articles

Categories: Climate change | Oceanography | Physical oceanography | Effects of global warming

 

The above information uses material from Wikipedia and is licensed under the GNU Free Documentation License.
Some facts may not have been fully verified for accuracy. [Disclaimers]
This page was last archived by our server on Sat Jul 31 02:29:29 2010. [ refresh local cache ]
Displaying this page or its contents does not use any Wikimedia Foundation's resources.
The owners of this site proudly support the Wikimedia Foundation.

[Hide]▼
'Sea Level Rise' News
NASA Launches Mission To Track Polar Ice By Plane - NPR
news.google.com
NASA Launches Mission To Track Polar Ice By Plane

NPR

A place like Pine Island can play a big role in sea - level rise , Martin says, because it's where land ice gets added to sea ice. Sea ice is like the ice cube ...



and more »
Google News Search: Sea level rise,
Sun Nov 1 14:59:07 2009
'Sea Level Rise' Images
Global Sea Level Rise Risks png
globalwarmingart.com
Global Sea Level Rise Risks png
1091px x 2000px | 226.60kB

[source page]

Looking at the whole world at the rate we are going I d say it will take awhile click for a very large image

Yahoo Images Search: Sea level rise,
Wed Jul 14 05:54:12 2010
'Sea Level Rise' Blogs
Impact of sea level rise in Bangladesh - Maps and Graphics at UNEP ...
maps.grida.no
Impact of sea level rise in Bangladesh - Maps and Graphics at UNEP ...

UNEP/GRID-Arendal

Fri, 01 May 2009 19:34:55 GM

Impact of . sea level rise. in Bangladesh. three maps in a time relapse resulting in 18 million people affected, 22000 km2 of land submerged by flooding.

Google Blogs Search: Sea level rise,
Sun Nov 1 03:35:27 2009
'Sea Level Rise' Answers
To what level will the sea level rise when all the ice melts.?
Q. I need to decide where to build my house so it becomes beach front property. Jenny, what about the ice on Greenland, Russia, Canada, Alaska and Antartica? this is my dream, it has to happen.
Asked by Stinky Badger - Fri Dec 28 14:49:07 2007 - - 6 Answers - 0 Comments

A. youll'be supprised it isnt only Badgers whos gonna vanish, but ive got escape plans set up, arrrgh
Answered by . - Fri Dec 28 15:47:36 2007

Yahoo Answers Search: Sea level rise,
Tue Apr 27 20:46:55 2010
[Hide]▲