Cryosphere science research and development (R&D) has been strongly committed to public service, integrating natural sciences with socioeconomic impacts. Owing to the current shift from purely natural cryosphere scientific research to linking cryosphere science with socioeconomic and cultural science, cross-disciplinary research in this field is emerging, which advocates future cryosphere science research in this field. Utilizing the cryosphere service function (CSF), this study establishes CSF and its value evaluation system. Cryosphere service valuation can benefit the decisionmakers' and publics awareness of environmental protection. Implementing sustainable CSF utilization strategies and macroeconomic policymaking for global environmental protection will have profound and practical significance as well as avoid environmental degradation while pursuing short-term economic profits and achieving rapid economic development.
Cryosphere; Service function; Value evaluation; Evaluation framework
The cryosphere refers to the portion of the Earths surface that is in the form of ice, including mountain glaciers, ice sheets, ice shelves, sea, lake or river ice, snow cover, permafrost, and seasonal frozen ground. As an integral part of the climate system, the cryosphere responds the quickest to and is the most representative of global climate change. It also impacts both bio- and anthropogenic systems on different spatial and temporal scales. The cryosphere interacts strongly with the atmosphere, land surface, biosphere, hydrosphere, and anthroposphere (human system). It plays an important regulatory function to the climate and Earth systems by sophisticated positive and negative feedback processes of water, energy, and material exchange on the different spatial and temporal scales (Qin and Ding, 2010 and Marshall, 2011). Because the cryosphere stores a significant amount of water, energy, and gas as well as carries endemic biological species and indigenous cultural structures, it is not only an irreplaceable resource but also a candidate for sustainable development of population, resources, environment, social and economic systems at high altitudes and polar regions. Therefore, the cryosphere has unique service function.
The cryosphere service function (CSF) plays an important role in the preservation and vitality of the general ecosystem. The CSF should also be considered as an important component of ecosystem services. CSF values should be measurable and calculable. Previously, cryosphere science research mainly focused on the study of its natural properties including the cryosphere process, mechanisms, and negative socioeconomic impacts (e.g., sea-level rise and cryosphere disasters). However, CSFs positive contributions to human wellbeing have not received sufficient attention nor have they been formally defined or systematically discussed. In this study, we define the CSF as a variety of services or benefits that the cryosphere system can provide to humans. Owing to its special characteristics, the cryosphere has recently been exclusively studied for its service functions and values. There is significant population and economic potential in polar, alpine, and nearby regions. Peoples livelihoods in such regions are highly dependent on water resources, suitable living environments, various tourism services, indigenous cultural structure, and the unique biological habitat related to the cryosphere. Ecosystem service (ES) assessment studies have developed rapidly in recent years (Peters et al., 1989 and WRI (World Resources Institute), 2005), achieving significant progress and establishing relatively advanced assessment methods; this has built a solid foundation for a sophisticated description of the value of ESs in the future. However, because of the often remote locations and little public awareness, the cryosphere service (CS) value of glaciers, snow cover, permafrost (tundra), and other elements do not receive long-term and adequate attention. In addition, the CSF is hardly considered in the ES valuation.
The cryosphere is widely distributed around the globe and most of its components are extremely sensitive to climate change. The CSF and its values are highly variable depending on the different spatial and temporal scales. Therefore, assessment studies of the CSF and its values must be based on cryospheric scientific principles. Furthermore, economics and sociology, the ethical ramifications of the specific CSF study, and the distribution pattern of the different cryospheric components on various spatial and temporal scales should be taken into account. This study aims to accurately identify the CSF and the differences and similarities among different regions and establish an appropriate value assessment system for different CSF areas. We then systematically evaluate the different service functions and their values to the cryosphere. These studies on the CSF values are aimed at identifying the market value of the CS, which will provide valuable information on the CSF contributions for decisionmakers. These studies are also important for promoting global socioeconomic health and sustainability, ecosystem construction and preservation, and avoiding the short-sighted economic decisions made by the government. The human influence on CSFs is another important aspect of the study in terms of globally sharing and bearing mutual CSF rights and responsibilities between the beneficiary and victimized countries or regions.
CS is defined as the benefit that the cryosphere provides to human society. Similar to the ecosystem function and its services, the cryosphere function reflects its inherent qualities. The CSF, on the other hand, reflects its socioeconomic impacts. That is, the CSF requires a human element, which includes livelihood and overall wellbeing, with the increasing dependency on environment resources. CS recognition and preservation by humans will gradually increase with the rise of economic development and living standards. Certainly, not all cryosphere functions are necessarily able to provide service. As mentioned above, CS represents the benefit that people can gain (e.g., recourses, products, and welfare) from the cryosphere. Here, we classify the different services of CS as supply, accommodation, social culture, and living environment service; all these products and services benefit peoples livelihood and wellbeing (Fig. 1).
Cryosphere service function for human wellbeing.
The solid cryosphere is a major source and supplier of freshwater to humans. Statistically, Antarctica stores 72% of the worlds available fresh water, which amounts to 27 million km3 of ice and snow; although, at present, it is difficult to access and utilize water from the polar ice sheets. However, the cryosphere provides precious water to sustain global ecosystems, industry, and agriculture over some arid lands. Meltwater is crucial for residents living in high mountains and polar regions (Hock, 2005). For instance, glacier coverage significantly influences river runoff in central Asia. Meltwater from mountain glaciers accounts for 25%–29% of total runoff in the inland arid areas of Northwest China; the proportion is up to 40% over the Tarim River Basin (Yang, 1991 and Gao et al., 2010). On the other hand, snow is an important source of water in the mountain regions all over the world. Mountain snow cover has provided freshwater for nearly 1/6 of the worlds population. Most arid regions in the western United States and central Asia are highly dependent (about 75%–85%) on snowmelt resources for public usage and agricultural activities (Payne et al., 2004, Barnett et al., 2005 and Barlow et al., 2005). In western China, the melting snow in the spring accounts for over 38% of average water resources.
Since the cryosphere is mature at remote high latitudes and altitudes, away from anthropogenic impacted areas, relatively clean air guarantees high-quality drinking water. Recently, commercially available sources of high-quality glacier water have become widespread around the globe and include many mineral water brands such as Evian mineral water in France, Heidiland mineral water in Switzerland, Alaska glacier water in America, Eska glacier water in Canada, the 5100 Tibet Glacier and the Kunlun Mountains mineral water in China.
Clean energy from the cryosphere mainly consists of glacial hydropower and natural gas hydrates. Meltwater runoff has served as a reservoir over steep terrains for hydropower production. For instance, many glacial valleys, fjords, and mountain areas in the Alps, Norway, western United States, and Canada have built numerous hydropower stations. The hydroelectric generation relies on abundant water resources from snow and ice and has stimulated regional industrial and agricultural development (Cherry et al., 2005). There are no estimations available for the total hydropower potential of global meltwater from western China. As a result of global warming and water preservation, the need for dam construction in mountainous regions is becoming dire.
Gas hydrate, which is widely distributed in the permafrost, submarine sediments of the continental shelves, and deep lake sediments, is a potential clean energy source. Natural hydrate is highly concentrated and volatile, has high storage capacity, and is freely emitted. In principle, 1 m3 of gas hydrate can be converted to 164 m3 of natural gas and 0.8 m3 of water; hence, exhibits high energy efficiency. Currently, the total estimate of gas hydrate is 1013–1016 m3 in global permafrost and 1015–1018 m3 in marine environment (part of them is the submarine permafrost) (Sloan and Koh, 2003 and Wu and Cheng, 2008), this value is equivalent to more than twice the worlds total known gas reserves. Following the United States, Canada, and Russia, China is the fourth country to discover natural gas hydrate physical samples in permafrost regions. Gas hydrate contributes positively to the optimization of the energy consumption structure.
The cryosphere plays a role in mediating global and regional climate owing to its high albedo and cold water, which drives ocean circulation, leading to a comfortable living condition and stable planetary ecosystem. The polar cryosphere acts as an air conditioner for the Earth. The cryosphere plays a pivotal role in the adjustment of the global climate system (Barry and Gan, 2011). Climate models suggest that the global climate regime would shift greatly if there were no polar ice sheets and sea ice, having a detrimental impact on the ecological system and food chain and eventually threatening humans. On the other hand, the Northern Hemisphere cryosphere, especially in permafrost zones, regulates the global climate system by acting as a carbon sink or source, which alters atmospheric greenhouse gas emissions. The organic carbon storage of the cryosphere surface (0–3 m) and deep layer (approximately 25–50 m in some areas) in the Northern Hemisphere is 1400–1850 Pg C. In total, the northern circumpolar permafrost region contains 1672 Pg C, which amounts to approximately 50% of the reported global underground organic carbon pool (Tarnocai et al., 2009). Because the cold and wet climate environment would limit the decomposition of permafrost soil organic matter, most soil organic carbon would accumulate (Mc Guire et al., 2009 and Mc Guire et al., 2010). Many studies have suggested mountain glaciers and polar ice caps as large organic carbon reservoirs. Glaciers store about 6 Pg C, which are mostly stored in the Antarctic ice sheets (Hood et al., 2015).
The cryosphere is an important source for rivers in mid- and low-latitude mountains, which naturally adjusts to runoff, and is referred to as a solid reservoir. Compared with noncryosphere regions, which are controlled by precipitation, cryosphere runoff is mainly controlled by temperature. With increasing temperature, ice, snow, and permafrost melting may accelerate, leading to an increase in runoff. Among them, ice, snow, and frozen ground have certain adjustments to runoff in the water cycle. Because of its seasonal characteristics, runoff from snow mainly plays a seasonal adjustment role. Mountain glacier runoff can range from interseasonal to centennial. The time scale for releasing or adjusting to discharge from underground ice in the permafrost is longer. Glaciers have a purpose for adjusting to the seasonal variations of river runoff, the so-called “peak-clipping and valley-filling” effects in the runoff chart. However, with continuous melting of glaciers, glacial water resources and river regulation will eventually be nonexistent (Kang, 1983, Liu et al., 2006, Yao and Yao, 2010 and Li et al., 2010).
The water conservation function of the cryosphere is remarkable. Among all components, frozen ground is the most essential and is closely related to terrestrial ecology. Owing to water impermeability in frozen ground and moisture transfer onset by a temperature gradient, there is some ground water near the permafrost upper limit. It is estimated that ground ice stores more water than mountain glaciers globally. Mountain glaciers account for only 0.12% of global freshwater resources, whereas frozen ground ice accounts for 0.86%. This significant water conservation is an important water resources for future sustainability. Preliminary estimates indicate that the total ground ice reserves in the permafrost regions of the Qinghai-Tibetan Plateau are approximately 9528 km3, which is roughly equal to 1.7 times the total amount of glacier ice in China (Zhao et al., 2010). Frozen ground is important for maintaining ecosystem stability in cold regions. According to the temperature and precipitation combinations in typical climate zones, without the water conservation and thermal effect in frozen ground, only a desert ecosystem can develop in the Qinghai-Tibetan Plateau instead of large areas of alpine meadow and wetland ecosystems. Owing to the huge water and heat effect of the permafrost in pan-Arctic regions, typical polygonal tundra and taiga ecosystems develop.
The cryospheres aesthetic value, which promotes cryospheric tourism, is one of the major factors of cryosphere tourism attractions. The aesthetic value mainly refers to the cryosphere landscapes artistic characteristics (e.g., shape and color), status, and significance (e.g., diversity, oddity, pleasure, and integrity). With its distinct monopoly on aesthetic value, the cryosphere landscape cannot be copied. The cryosphere contains many different elements including glaciers, glacier relics, ice sheets, ice shelves, sea ice, snow cover, frost, frost heave, snow cover, freezing rain, freezing fog, ice sculptures, and other related aesthetic and cultural characteristics, which are important tourist attractions and play significant roles in recreational service. Owing to the rise in economic and living standards and more leisure time, cryosphere tourism has become a new and integral part of many countries' development strategy around the world. Cryosphere tourism plays an important role in advancing regional economic benefits, enhancing the meaning and popularity of regional tourism, and promoting regional economic and social sustainability.
The objectives and purpose of cryosphere scientific research and environmental education are primarily reflected in the improvements to the national economy and peoples welfare. Examples of environmental education include activities such as cryosphere scientific research (theoretical research), popular cryosphere knowledge, application of cryosphere technology, cryospheric environment education, and training cryospheric researchers. The cryosphere is an important resource for studying past climatic and environmental changes, and thus an important media for climate change research. Some cryosphere parameters (e.g., snow cover area, snow depth and water equivalent, sea ice extent and concentration, permafrost temperature and active layer thickness, moisture, and heat flux) are also essential variables for operational studies such as weather forecast and climate prediction. Moreover, the dates of river ice freezing and thawing, frozen section, the thickness of river ice, and so on are crucial input parameters for ice flood warning/forecasting in hydrological services. The prevention of cryosphere disaster, spring flood forecasting, maintenance of coastal harbors in cold regions, maintenance and safe operation of road network and infrastructure in permafrost zones, route planning of icebreakers in polar regions, and so on require cryospheric observation and prediction products in order to provide basic services. The cryosphere is extremely sensitive to climate change; thus, it is usually a good natural indicator for detecting climate change and has a high value for science and environmental education. Through popular science education and tourism to regions associated with the cryosphere, the general public not only understands the formation and evolution of the cryosphere but also respects environmental protection.
On account of its ancient history and culture, many snow-covered and glacierized mountain peaks are considered as spiritual and accorded cultural importance; they are considered to be the physical manifestation of different gods and spirit, and their presence contributes to a unique cultural structure, understanding, and worship of mountainous residents. For example, Mt. Qomolangma (Mount Everest) means goddess in the Tibetan language, and in Nepal, it is called Sagarmāthā, meaning the god of the sky. In India, thousands of pilgrims traverse the Gangotri Glacier as a sacred spot (Epstein and Peng, 1998, Litzinger, 2004 and Wang and Qin, 2015). In Peru, the natives believe that spirits live in the mountains. Some indigenous Peruvians associate the loss of ice and snow from mountain peaks with the gods departure and the end of the world (Steinberg, 2008). Similarly, in Canadas Yukon Territory, the indigenous people consider glaciers as gods that could perceive human activities. Moreover, the cryosphere is home to some of the most unique cultures in the world. For example, Eskimos live year round in the Arctic and central Arctic cryosphere and their ways of living closely relate to the cryosphere, which forms a unique sociocultural structure. These generations live in the cryosphere area and their humanistic characteristics are inextricably closely related to the presence of the cryosphere. The unique cultural structure of these minorities undoubtedly depends on the availability of cryospheric resources and unique landscapes. In the context of global warming and the impacts of globalization and modernization, the question of how to keep or protect humanity and the indigenous cultural structure in cryosphere regions has become an important project for the United Nations Educational, Scientific and Cultural Organization (UNESCO) and humane studies. On the other hand, the cryosphere, with its own unique charm, provides inspiration and materials for artistic creations in literature, film, photography, logos or signs (e.g., totems and trademarks), sculpture, architecture, and such for humans (Wang and Jiao, 2012 and Vergara et al., 2007). For example, the novel The Snows of Kilimanjaro by Ernest Hemingway, the movie series Ice Age 1–4, and other literary works are derived from elements of the cryosphere.
The cryosphere provides food, water, and the shelter needed for the survival of different species. It not only provides a large area for different habitat services for permanent residents and migratory populations in cold zones over the world but also provides rich living spaces with heterogeneity and a variety of habitats or refuges for feeding, breeding of terrestrial and marine biota, and residents living in the vicinity of the cryosphere. Furthermore, the cryosphere is a safe haven for unique or rare and endangered wildlife. In polar and sub-polar regions, in addition to indigenous people, the cryosphere maintains crucial habitats for microbes, algae, worms, crustaceans, sea birds, penguins, seals, walruses, polar bears, and whales (UNEP, 2007). For example, ice algae that grow onto sea ice and under ice are important food sources for organisms in the Arctic and Southern oceans. Under-ice crustaceans are the key species for material and energy flows from sea ice to the water body. The composition, distribution, and abundance of under-ice crustacean species are closely related to the age, type of sea ice, and under-ice form. Sea ice provides an extreme and variable habitat and shelter for different types of ice-related biota. The supported sea ice biomes play a vital role in the polar ecosystem (ACIA (Arctic Climate Impact Assessment), 2004, UNEP (United Nations Environment Programme), 2007 and Poulin et al., 2011). As another example, snow cover in the Arctic and sub-Arctic provides a medium that supports migration routes, breeding, and refereeing shelter for small animals (e.g., birds, small mammals, rabbits, and foxes) via a smooth undulating terrain. In addition, the interaction between the cryosphere and ocean create another livable habitat. Cryospheric water promotes the circulation of cold and warm ocean currents in high latitudes as they flow into the ocean. When the cold and warm ocean currents intersect, seawater disturbance occurs, i.e., the near-surface seawater sinks, whereas deep water ascends. The seawater that flows to the surface carries nutrients to the ocean surface. These nutrients accelerate the growth of plankton, which thereby flourish and provide a rich food source for fish. At the same time, the junction belts of the cold and warm ocean currents create a water barrier to prevent fish from swimming away, which is beneficial to form large-scale fishing grounds including the worlds three major fishing grounds in Hokkaido of Japan, the North Sea of Europe and Newfoundland of Canada (see Fig. 1).
The diverse CSFs determine their various service values as per the taxonomy of the ES value in terms of the way, degree and duration that human obtained benefit, the CSFs value can be categorized into use value (UV) and nonuse value (NUV). Use value includes direct use value (DUV) and indirect use value (IUV), and nonuse value comprises optional value (OV), existence value (EV), and heritage value (HV). Direct use value refers to the value provided directly to the cryosphere from human activities including the output (e.g., freshwater resources and clean energy values) and nonoutput values with noncompetitive and nonexclusive services (e.g., aesthetics and recreation, scientific research, environmental education, religious, and cultural values). Conversely, indirect use value refers to the benefits indirectly obtained from the cryosphere. Indirect use values are not influenced by human activities such as climate regulation, runoff regulation, water conservation, and ecological regulation services of the cryosphere. Optional value refers to the potential value of the cryosphere resources. It features some resources and services that are likely to be used. Heritage value is a manifestation of some use value and nonuse value of the CSs reserved for the descendants, namely, values that pay for the descendants using CSs in the future. Existence value, also known as an intrinsic value, ensures that CSs can persistently exist. EV is the inherent value of the cryosphere and is not concerned with the use of CSFs now or in the future. The assessment results are shown in Table 1, detailing the cryosphere function and its service value. For supply service value (e.g., freshwater and clean energy) can be determined directly using market price method (MPM), while other non-material service value (e.g., regulating service, social and cultural service, habitat service) can only be calculated by replaced or stimulated market methods. The available replaced or stimulated methods include opportunity cost method (OCM), shadow engineering method (SEM), hedonic pricing method (HPM), travel cost method (TCM) and contingent valuation method (CVM). Overall, the evaluation system is composed of four primary and nine secondary indicators.
|Service functionclassification||Evaluation method of service function value|
|Direct use value||Indirect use value||Nonuse value||Evaluation difficulty|
|Supply service||FreshwaterResource||Market price method||Relatively easy|
|Clean energy||Replacement cost method||Relatively difficulty|
|Regulation service||Climate regulation||Replacement cost method, Wish to pay, hedonic pricing method||Difficulty|
|Runoff regulation||Shadow engineering method||Difficulty|
|Water conservation and ecological regulation||Shadow engineering method, replacement cost method, market price method||Relatively difficulty|
|Social and cultural service||Aesthetic and recreational service||Hedonic pricing method, Wish to pay, travel cost method||Relatively easy|
|Scientific research and environmental education||Cost analysis method||Relatively easy|
|Religious and cultural service||Cost analysis method, Wish to pay||Relatively difficulty|
|Habitat service||Habitat provision||Opportunity cost method, Contingent valuation method||Relatively Difficulty|
On the basis of the existing knowledge and degree of understanding, this study preliminarily discusses CSFs and establishes a CSF evaluation system in terms of the CS features. In consideration of our study and similar research in the fields of CSFs and ESs, CSF research may need to highlight the following two aspects in the near future:
The following three points related to the CS value calculation method should be addressed:
How to fully analyze and characterize the CS content and its formation mechanism, and how to summarize the basic CS theory and its value assessment? How to identify and mechanistically describe the relationship between cryosphere processes and CSFs? These questions will be of significant scientific importance for future studies. During the initial stage, we will start with typical cases, choosing some relatively direct and clear CSFs to systematically evaluate the CSF and its principles. This will lay a good foundation for estimating the overall CSF values on a national scale in China as well as on a global scale.
This work was funded by National Basic Research Program of China (2013CBA01804, 2013CBA01808), Technology Services Network Program (STS-HHS Program) of Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, and the independent subject from Stake Key Laboratory of Cryospheric Sciences, Chinese Academy of Sciences. We also thank Mrs. Yang Jiao for her helpful comments and suggestions, which have considerably improved the final manuscript.