Relationship Between Global Warming and the Sea Level Rising

An increase of the level of the sea is known to be one of the most significant and long-lasting results of climate alteration, specifically global warming. The whole world’s attention is focused on high forecasted rates of possible future increase of the sea level. It is extremely essential to mention that countries and small islands that are situated in low-lying locations are concerned that their land might be endangered because of flooding of the waterside, which provokes many people to migrate to other countries. Thus, the influence of apparent climate change on rising level of the sea appears to have heightened international attention. Global warming caused by climate changes might lead to an elevation in present rates of water levels, resulting in flooding numerous low-lying waterside and tidal areas. Moreover, rising sea-level might also have considerable negative implications for organisms that rely on above-mentioned locations, including shorebirds that need these locations as habitat during winter and migrations. Therefore, the current paper will demonstrate the relationship between sea-level increase and global warming.

On the one hand, sea level alteration is known to be a naturally appearing procedure. The world experienced solid glacial maximum more than 18,000 years ago. Since that period, the melting process has been taking place because of the natural global warming, which led to the elevation of the sea-level. Due to the fact that this has been the natural global warming, all of the processes have not led to disasters. On the other hand, current global warming depends on human-provoked activities, including fossil fuels burning, deforestation, agricultural operations, etc. This type of global warming is accountable for the general mass of increasing water levels, specifically impacting the upper ocean layers. Therefore, currently, such natural forces as volcanic activity and solar radiation are accountable for minor amount of present global warming, and especially upper ocean’s share of warming-generated, also known as thermosteric, sea level increase. Despite the fact that greenhouse gases, which appear from human activities, are known to negatively influence the nature, many researchers state that the process cannot lead to a disaster as the world is changing, and innovations compared with altering engineering will help to cope with such issues. Nevertheless, a number of small islands currently have problems connected with rising sea-levels, especially land and coastal erosion. In addition, the past and incessant shifts in a multitude of floating ice sheets, which are impacted by global warming, lead to alterations in the vertical land movements and gravitational field. Therefore, these movements lead to changes in the ocean level in comparison to the land levels. Therefore, large-scope alterations, which are combined with local tectonic movements, might negatively impact the regional sea-levels.

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Global warming has elevated the sea level and will proceed doing this. This is the consequence of the ocean water broadening in the process of its heating, which is combined with the ice caps and glaciers melting. The sea level changes with space and time because of physical processes, including waves and tide. Average level of the sea at a specified stance can be outlined as the altitude water rim aggregated over some time-period, which is sufficiently long to remove the fluctuations provoked by waves and tide. In fact, the world contains a specific quantity of water. Jim Ball believes that this quantity of water cannot be elevated or decreased either by anthropogenic or environmental impacts. This is explained by the fact that water can be investigated in all its discrepant conditions, including fluid, vapor, and firm state at any point in time. The huge amount of earth’s surface is covered with ice, which is majorly situated near the Polar Regions. The rim of the ocean is majorly in fluid condition, but some areas surrounding Antarctica together with the Arctic Ocean are covered with seawater (brine) ice with snow topping. Water in solid state can also be found on land. Antarctica and Greenland is practically completely covered with ice sheets for thousands of meters. For example, the Greenland glaze actually coats a location of approximately 1.8 million km2. This stands for approximately seven-eighths of the whole island. On the other hand, the Antarctic ice sheet covers an area of approximately 13 million km2. In fact, above-mentioned glaze appears to be thicker when compared to the Greenland’s one and might even reach the level of 4000 m in thickness. Therefore, Antarctic appears to be the biggest worlds reserve of fresh-water. Thus, such huge areas of the earth covered with ice contain huge amount of water. Therefore, in case these huge amounts of ice changed from solid state to liquid one, a large quantity of water could be released into the oceans. An essential amount of energy is needed for this to happen, meaning that there should be a change in global temperatures to higher ratio.

Global Warming and the Elevation of Level of the Sea in the Past

Water levels elevated comparatively slower during the last 6000 years. The facts demonstrate that it is possible to define the sea level 2000 years before now through the general analyzing of aquariums, which were created by ancient Romans. Due to the fact that these tanks were supposed to be at sea level for the floodgates to be capable of operating, researchers are able to accurately evaluate water levels within their utilization time. The juxtaposition of these levels with achieved documents demonstrates that there has been practically no alteration in sea levels starting from 2000 years before now till the beginning of the 19th century. Alterations in regional sea level evaluated from precipitate substances gathered in salt backwaters cause a ration elevation of water levels in the eastern and western Atlantic Ocean within the transition period of 19th-20th century. The coastal and island tide data selected during the last several centuries demonstrate that sea level increased by merely less than 20 cm in the period between 1870 and 2001, with a medium elevation of 1.7 mm annually during the 20th century. This data appears to be consistent with the geological information and a number of continued accounts and documentations of water levels selected from waterside tide meter. Starting from 1993 and ending with 2006, nearly worldwide estimations of water levels (particularly between 65°N and 65°S) taken with a help of elevated accuracy satellite height indicators demonstrate that worldly average water levels have been elevating at “3.1 ± 0.4 mm” annually. The above-mentioned rate appears to be faster in comparison to the medium ratio of elevation for the previous century, which successfully stood for a system and sequence of dimension greater compared to the rate of elevation during the two millennia before the 18th century.

Sea-Level Alteration Contributions and Global Warming

The two major causes of water levels increase stand for the thermic broadening of sea water when it warms, and an elevation of the waters volume, especially from earth-grounded ice sources, including caps, snow-fields, together with the ice sheets of Antarctica and Greenland. The global warming caused by elevating greenhouse gas density appears to be an essential driver of two above-mentioned contributions to the sea-level increase. In the period between 1955 and 1995, ocean thermal broadening actually contributed to approximately 0.4 mm of sea-level increase yearly. In fact, the most accurate data is available for the period between 1993 and 2003. It was the time when thermal broadening was evaluated to be essentially greater, at approximately 1.6 mm for the upper 750 m of the ocean alone annually. Levermann  et al. prove that the dissolution of ice caps and glaciers (exempting the glaciers nearby Antarctica and Greenland) contributed to sea-level increase by approximately 0.3 mm each year in the period between 1961 and 1990 rising to almost 0.8 mm in the period between 2001 and 2004. Casper believes that the ice sheets of Antarctica and Greenland appear to have the possibility to seriously endow to level of the sea increase. Nevertheless, they appear to be the biggest origin of incertitude as well.

Global Warming and Sea-Level Increase During the Previous Century

Starting from 1990, the world observed the raised snow agglomeration at solid increase in regards to the Greenland glaze; at the same time, there has been more prevalent rim dissolution and a solid elevation in regards to outstream snowfields at decreased rise. The net outcome show reduction in the amount of the Greenland glaze, leading to a staid endow to water levels elevation. In fact, the uncertainty is higher in regard to the Antarctic glaze. The facts demonstrate that there is no sufficient information in order to make direct evaluations for the preliminary decades. Currently, the aggregate acquisition of the Antarctic glaze because of the elevated condensation of the East Antarctic glaze cannot indemnify for the massive detriment because of the elevated glacier observed currently “on the Antarctic Peninsula and the West Antarctic Ice Sheet”. The modeling researches assume that the Antarctic glaze appears to be hitherto reacting to alterations starting from the glacial episode during a past geological period and that this might also contribute to sea-level increase. The discrepancy between the quantum of the contributions to sea-level increase and the estimated elevation starting from 1993 and ending with the current times is smaller in comparison to the evaluated errors. Nevertheless, in the period between 1961 and 2003, ocean thermal broadening together with the dissolution of ice caps and glaciers and a prudent allotment for an ice sheet contribution cannot affluently and sufficiently account for the demonstrated increase. Potential causes for this disparity incorporate the improper ocean database, especially for the deep and Southern Hemisphere oceans, resulting in an underestimation of ocean thermal broadening and improper evaluations of the cryosphere. Alterations in regards to the water preservation on earth, encompassing shifts in lakes, construction of dams (both small and large ones), infiltration into water beds, and ground water mining, might also be essential. Nevertheless, the extent of these contributions appears to be obscure. Thus, model studies demonstrate that essential inconsistency from year to year of the climate-connected constituent of terrestrial water storage have minor long-range tendency.

The facts demonstrate that anthropogenic activity, especially industrialization, agricultural operations, and deforestation accentuate global warming and greenhouse effect. On the one hand, industrialization and its gas emissions cause 77 percent of greenhouse effect leading to global warming. On the other hand, such land usage alterations as agricultural methods and deforestation cause 23 percent and 9 percent of global warming accordingly. These activities can result in climate and climate-connected alterations in the earth setting and atmosphere setting. An enlarging concentration of GHG (greenhouse gases), especially CO2, methane, and nitrous oxide provokes the alterations in atmosphere, leading to global warming. Global warming, in its turn, influences the rise of sea-levels because of warming high latitude areas, where the major part of global ice can be found.

The average yearly atmosphere and earth temperature has elevated by approximately “0.5◦C during the 20th century”. This elevation actually caused appreciable increase in global sea level ranging from 10 to 15 cm. Thermostatic sea level increase leads to the rise in ocean altitude provoked by the elevating quantity of the ocean, which appears when sea-water warms and broadens. The facts demonstrate that starting from 1970, the global sea level has been elevating by 2mm each year due to the fact that global warming was leading to the temperature rise in all ocean layers. More than half of the overall increase, standing for 46 mm, appears from thermal amplification, especially in the upper-ocean layer, which accounts for the upper 700 meters of sea-water. The remaining part of the elevation in global sea level is provoked by melting ice (also caused by global warming), and alterations in reservoir levels. The study by Courchamp et al. demonstrates that the top layer of the ocean is warming majorly because of human activity. It actually presupposes that all outcomes of the global warming, encompassing rising sea level, are caused by human activity and not natural processes. Hansen, Sato, and Ruedy revealed that human activities and operations were accountable for an elevation in thermosteric sea level of 40 mm annually between 1970 and 2005 compared to an elevation of 46 mm annually during the analogous period as a consequence of both natural changeability and human processes. This actually presupposes that 87 percent of the demonstrated global thermosteric sea level increase of the upper water column of the ocean starting from 1970 is connected with human processes and operations. In fact, it is obvious that the discrepancy is highly big, which means that the influence of human activity is apparent. This research also demonstrates that human impact on thermosteric sea level increase differs by area and region. Human operations and processes are accountable for all of the elevation in thermosteric sea level increase in the Southern Ocean and the Tropical Pacific, while the natural inconsistency and changeability stands for 35 percent of the warming in the North Atlantic. Ball states that despite the fact that the concentration of aerosol and greenhouse gas emissions has elevated global ocean temperature, the whole ocean does not warm at the analogous rate. It is important to mention that alterations in wind circumstances and ocean circuit can negatively impact the quantity of heat that each ocean region consumes and distributes around the globe. Each ocean region appears to have individual features and might react discrepantly to global warming.

It appears that Mount Kilimanjaro, being Africa’s tallest mountain, has forfeited 75 percent of its glacier sheet starting from 1912, and its ice might completely vanish in 15 years. In addition, Lake Baikal in Siberia demonstrates a tendency to freeze soon enough, which is not in line with statistics revealed a century ago. Moreover, Venezuelan mountaintops used to have six glaciers in 1972, while currently there are only two of them. It is obvious that above-mentioned geophysical alterations have an influence on sea levels. Nevertheless, a possible 1-meter elevation in the level of sea in such countries as Bangladesh might be caused by both global warming, groundwater removal, and land movements.

Threats of Sea-Level Rising

In fact, greater sea levels threaten groundwater supplies and coastal communities. It should be mentioned that 40 percent of the global population dwells in such coastal locations. There are two main mechanisms in these coastal communities, which provoke the increase of sea levels. Firstly, land ice, including polar ice sheets and glaciers, is shrinking, releasing water into oceans. Secondly, due to the fact that ocean temperatures elevate, the warmer water broadens. As coastal communities are trapped within a basin restrained by the continents, the water can practically only elevate. Moreover, a number of parts of the world, particularly low-lying river deltas, experience the submerging of local land (the process known as subsidence). There are five major consequences of sea level rise. Firstly, coastal communities dwell within 100 km of the ocean, placing high quantities of lives and highly expensive infrastructure and property at great hazard. Secondly, global warming causes storm surges and high tides at constantly-elevating seas, threatening people and coastal infrastructure. Thirdly, high tides provoked by global warming threaten natural protections against impairing storm affluxes. The majority of natural protections, including barrier islands, sand dunes, beaches, salt marshes, etc., decrease inland because of the elevation of the sea level. In addition, all above-mentioned natural protections can be washed off or drowned. Fourthly, high tides provoked by elevated sea-levels increase the level of erosion at beaches, wetlands, and engineered structures. Finally, a sea-level increase can presuppose saltwater coming into subsoil water drinking reserves, polluting watering reserves, or invading farming/agricultural fields. Thus, global warming provoking sea-level rise is specifically dangerous in terms of contamination of freshwater supplies in low-lying, gently sloping coastal locations.

Longer-Range Projections of the Relationship between Global Warming and Sea-Level Rising

The ration of the level of the sea increase will be partially defined by previous emissions, and it does not solidly depend on 21st century GHG emission during next decades. Nevertheless, sea-level forecasts close to and beyond 2100 are solidly sustained by the future greenhouse gas emissions. Thus, ocean thermal broadening and the ice sheets might feasibly contribute to a considerable sea level increase because of greater greenhouse gas emissions. For instance, the analysis of the Greenland’s glaze demonstrates that in the case the global medium temperatures cross a point in the range between 1.9°C and 4.6°C higher than the pre-industrial valuables, it will lead to the surface dissolution surpassing possible precipitation. The irreversible consequences might lead to an incessant contraction of the Greenland Ice Sheet over a period of centuries and millennia. The above-mentioned consequence appears to be consistent with observations, which show that the global sea level in the past interglacial period used to be several meters higher compared to the current level. This threshold of melting broadening precipitation might possibly be intersected in the late 21st century. Moreover, dynamical reaction of the West Antarctic Ice Sheets and Greenland might result in a more significant rate of sea-level increase in comparison to the surface, which melts alone.


The current paper demonstrates that despite different opinions, sea-level increase is greatly impacted by climate alterations, especially global warming. The paper dedicated much attention to countries and small islands due to the fact that they are located in low-lying locations and their land might be endangered as flooding and waterside might make a huge number of people migrate to other countries. A sea-level increase appears to be a global phenomenon, which means that the overall quantity of its affects might be immense, encompassing coastline washout, demission of waterside ecosystems and deficient operations of circumlittoral structures. Nevertheless, the generic evaluation of these affects appears to be currently restricted to a subcategory of the feasible influences, encompassing influx of population, land, and wetlands. Temperature rise appears to be a significant facet, which contributes to worldly level of the sea increase as warming concerns the top ocean rim hundred meters. The paper demonstrates that global warming seriously impacts land ice, leading to melting of both mountain snowfields and the glazes of Antarctic and Greenland. This dissolution affects sea-level and might put great pressures on society and can lead to numerous millions of environmental refugees. The world has to make maximum efforts in order to avoid possible huge increases in sea level. Thus, an essential lowering in greenhouse gas emissions is highly necessary. Nevertheless, the achievement of the necessary lowering in emissions might be challenging and requires insistent and stable commitment.