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Climate Change Assessment over the Arctic Region
Published in Neloy Khare, Climate Change in the Arctic, 2022
Due to sea ice melting in summer, dark open water areas are exposed, absorbing more heat from the sun (Figure 1.2). More ice melts due to excess heat. The sea ice’s loss is one of the Arctic amplification drivers (Figure 1.3) (Slivka 2012; Goldenberg 2012). Permafrost may also play a role in positive feedbacks. As the thawing of permafrost starts, plants and animals frozen in the ground begin to decay. Their decomposition releases carbon dioxide and methane back to the atmosphere. It can further induce warming. The shifting Arctic vegetation also affects the surface brightness and adds up to warming. More water vapour is held up due to more warming of the Arctic atmosphere, which is an important greenhouse gas (Slivka 2012; Goldenberg 2012). In the Arctic, warming is causing further warming in the following manner.
Communication systems and network technologies
Published in Kennis Chan, Future Communication Technology and Engineering, 2015
Ozone makes up only about 0.6 parts per million of the atmosphere by volume, but it is continuously created and destroyed in an endless photochemical Chapman cycle (Chapman, 1930), absorbing ultraviolet radiation to maintain an “ozone layer” between 15 and 35km above Earth’s surface. The stratosphere is heated daily primarily by continual dissociation of molecular oxygen O2 and ozone O3 where the molecular/atomic pieces fly apart at high velocity, increasing the average translational kinetic energy of all gas molecules, which, according to the ideal gas law, increases the temperature of air. The optical thickness of this layer varies regionally by the minute, time of day, season, and latitude (WOUDC, 2014). Ozone tends to accumulate at the poles between mid-winter and early-spring when increasing sunlight forms ozone faster than it can be destroyed (Fig. 4) (Fioletov, 2008). More ozone during winter heats the lower stratosphere, causing very cold temperatures on Earth. Ozone depletion since 1970 is most noticeable during these times with total column ozone decreasing ∼50% each winter in the Antarctic ozone hole and less regularly in the Arctic but reaching 45% in 2011 (Manney et al., 2011). Less ozone cools the lower stratosphere and warms minimum surface temperatures. The greatest warming observed on Earth since 1970 was along the Antarctic Peninsula (Hughes et al., 2007, Mulvaney et al., 2012), central West Antarctica (Bromwich et al., 2013), and in southern oceans (Waugh et al., 2013) in late winter, early spring, all within the Antarctic ozone hole. The second greatest warming was in the Arctic (Jeffries and Richter-Menge, 2012), well-known as Arctic amplification.
The Climate System
Published in Julie Kerr, Introduction to Energy and Climate, 2017
Based on the extensive work that has been done to date, scientists have a clear idea of where conditions are going in the future. According to the United States Geological Survey (USGS), based on the information obtained from both tidal gauges and satellite measurements worldwide, scientists can say with confidence that sea-level rise has increased during the twentieth century. Based on the data acquired from Australia’s Commonwealth Scientific and Industrial Research Organization, data gathered from January 1993 to December 2015 shows that sea level has risen on average 3.3 mm/year (Figure 2.13). Increased scientific knowledge has also clarified some issues that were not well understood previously, such as that the large polar ice sheets are far more sensitive to surface warming that initially thought, with significant changes currently being observed on the Greenland and West Antarctic ice sheets. Scientists now realize that these melting ice sheets can add water mass much more quickly to the oceans than previously assumed and play a significant part in overall global sea-level rise. A notable consensus among specialists in climate change at USGS is also marked today. It is largely recognized and accepted that there could be a rapid collapse of the polar ice sheets, and scientists have keyed in on the fact that anthropogenic actions, such as burning fossil fuels, could result in triggering an abrupt sea-level rise before the end of this century. They stress public education and political policy be brought to the forefront in order to deal most effectively with a situation that affects every person living on earth now and in the future. Figure 2.14a shows the drastic decrease in ice coverage in the Arctic over the past 30 years—approximately half now of what it was in 1979. Today the ice extent is below 4 million square kilometers. Ice volume shows a comparable rapid decrease. Figure 2.14b shows the annual average temperature in the Arctic region from 1979 to 2012. Figure 2.14c illustrates the average sea ice extent from 1979 to 2012. Satellites have measured a warming trend of 0.53°C per decade; which is considerably higher than the 0.16°C per decade global temperature increase. Since 1979, the Arctic has warmed about 3.3 times faster than the earth in general. Referred to as the “Arctic amplification,” it is partially caused by the disappearance of sea ice and the effect this has on regional albedo (referred to as the ice-albedo feedback). Scientists recognize that greenhouse gases play a major role in the sea ice decline of recent decades (Hagelaars, 2013). Because of these relationships and effects, it is important that the scientific basis of climate change be well understood when dealing with the sustainable ramifications caused by climate change.
Routeview: an intelligent route planning system for ships sailing through Arctic ice zones based on big Earth data
Published in International Journal of Digital Earth, 2022
Adan Wu, Tao Che, Xin Li, Xiaowen Zhu
In recent decades, the Arctic has warmed two to three times as fast as the global rate due to the unique features in the Arctic climate system – a phenomenon known as Arctic amplification (Fang et al. 2022; Blackport and Screen 2020; Dai et al. 2019; Cohen, Pfeiffer, and Francis 2018). A warmer Arctic has been driving reductions in Arctic sea ice. For example, the sea ice extent decreased at a rate of – 4.0% every 10 years during the recent period of 2007–2020 (Thoman, Richter-Menge, and Druckenmiller 2020). The accelerating sea ice melt in the Arctic is opening up new polar shipping routes, such as the Northeast Passage (NEP) from the Pacific to the Northern Atlantic, along the Norwegian and Russian Arctic coasts. Compared with the traditional Suez Canal route, the NEP will shorten the journey by 40% and the sailing time by approximately 20 days (Yumashev et al. 2017; Zhu, Cao, and Ai 2018), thus creating a potential alternative route for global trade.
2014 summer Arctic sea ice thickness and concentration from shipborne observations
Published in International Journal of Digital Earth, 2019
Qingkai Wang, Zhijun Li, Peng Lu, Ruibo Lei, Bin Cheng
The Arctic plays a vital role in the climate system, as one of the Earth’s ‘three poles’ in addition to the Antarctic and the Qinghai-Tibet Plateau. However, data show that Arctic air temperature has increased at a speed more than twice the global rate because of the Arctic Amplification (Serreze and Barry 2011), while Arctic sea ice in this ocean has experienced dramatic changes in recent decades, including a consistent reduction in extent (Comiso et al. 2008; Stroeve et al. 2012), loss of multi-year coverage (Kwok and Cunningham 2010; Comiso 2012), and a reduction in thickness (Renner et al. 2014; Lindsay and Schweiger 2015). These changes have caused large fluctuations in the sea ice regime, leading to possible navigations as the Arctic ocean has become more accessible (Khon and Mokhov 2010; Liu and Kronbak 2010; Shibata et al. 2013). In each summer of recent years, Chinese container vessels have been able to pass through the Arctic passage to Europe. Indeed, subsequent to the proposal and future development of the Belt and Road Initiative, Arctic navigations between China and Europe is expanding.
New insights in sources of the sub-micrometre aerosol at Mt. Zeppelin observatory (Spitsbergen) in the year 2015
Published in Tellus B: Chemical and Physical Meteorology, 2019
Matthias Karl, Caroline Leck, Farshid Mashayekhy Rad, Are Bäcklund, Susana Lopez-Aparicio, Jost Heintzenberg
Arctic warming has proceeded twice as fast as the global average since the mid-1960s (Jeffries and Richter-Menge, 2015), a phenomenon termed Arctic amplification. This is worrying given the particular vulnerability of Arctic ecosystems to climate change. Surface radiative forcing and surface temperature response related to short-lived climate forcers (SLCFs) such as black carbon (BC), methane, tropospheric ozone (ACIA, 2004) is one of the causes for the Arctic amplification (Serreze and Barry, 2011). BC contributes significantly to the warming of the Arctic climate, directly through absorption of incoming sunlight and indirectly through the reduction of the albedo (darkening) of Arctic snow and ice surfaces due to BC deposition, thereby contributing to the rapid melting of sea ice in the recent decades (Hansen and Nazarenko, 2004). The Arctic lower troposphere is influenced by anthropogenic emissions from high-latitude Eurasia and by pollution from emerging sources within the inner-Arctic (region north of the Arctic Circle, that is the southernmost latitude in the Northern Hemisphere at which the centre of the sun can remain continuously above or below the horizon for 24 h). These pollution sources are currently poorly quantified (Roiger et al., 2015). These sources include emissions associated with flaring of gas during oil production (Stohl et al., 2013) and transit shipping activities (Dalsøren et al., 2013). Natural aerosols from inner-Arctic sources, such as sea spray, which comprises a complex mixture of inorganic salt and organic substances, and biogenic secondary sulphur have, in contrast to SLCFs, a cooling effect on the Arctic climate by scattering incoming radiation (direct forcing) and by changing of cloud albedo (first indirect forcing). Natural emissions affect the uncertainty in determining the aerosol first indirect forcing because they affect the background aerosol state against which the forcing is calculated (Carslaw et al., 2013). In order to evaluate the potential impact of the Arctic anthropogenic emission sources it is thus necessary to better understand the inner-Arctic natural aerosol sources and their transformation processes during their transport in the atmosphere on top of which anthropogenic aerosol exert their radiative forcing.