The Polar-Alpine biome includes the Arctic, Antarctic, and high mountainous areas in other words Alpine tundra across all the continents (“T6 Polar/alpine (cryogenic) biome,” n.d.). The Tundra biome mostly has harsh weather with cold and frozen landscapes consisting of cold and dry regions. Alpine tundra is located on the top of the mountains at very high elevations where the temperature drops below freezing overnight (“Tundra biome,” 2023). For this research, the paper will cover Alpine tundra.

The alpine tundra, situated at the highest elevations of mountain ranges, serves as a crucial source of freshwater during summer and spring and offers a habitat for unique species (Barredo et al., 2020). However, due to global warming, the global alpine tundra is at risk of decreasing rapidly with time and as the temperature rises it may disappear completely. This leads to one of this paper’s main research questions, i.e., considering the threat posed by global warming to the alpine tundra and its ecosystem, can we measure the damage of losing the biome if it cannot be reversed? The approximate monetary value calculated for this biome on a global scale will equal the damage as we lose the alpine tundra to global warming. The damage may be even more because the ecosystem impacts other natural resources.  This research question may help evaluate the economic significance of the biome and potentially enhance awareness about its importance. The data collected and the values calculated in the paper may underestimate the value of the biome, but the purpose is to foster awareness and, at the very least begin to address the issue. More importantly in this paper, the biome will be looked at from an economic lens and less from an ecologist’s perspective.

This research is crucial because global warming is increasing and this increase in temperature is damaging the alpine tundra and its ecosystem drastically. The next section of the paper will be methodology. The paper will continue with a literature review – First, research papers from the 20th century, that will highlight the global impact of the alpine tundra and its ecosystem due to climate warming, human behaviour and the contribution of the industrial revolution. Next, we move to research from the 21st century discussing the potential loss of European alpine tundra due to global warming and its consequences moving forward. Then, the paper discusses the threat to species, vegetation, and access to fresh water due to declining alpine tundra. Additionally, the critical role of snow cover in the alpine tundra ecosystem is examined. The paper will move to the methods and results section where the global value of the alpine tundra was calculated using data collected from the Ecosystem Services Valuation Database (ESVD) (Brander et al., 2023). Next, the paper will cover the discussion and conclusions and end with a future research possibility.

Approximately 3% of the Earth’s surface comprises of alpine tundra. As noted by Chaplin III & Körner (1995), species inhabiting alpine regions are specialized due to isolation and harsh climatic conditions, resulting in high species richness. However, the ongoing climate warming has caused the upward migration of alpine species, a trend expected to persist with continued warming. Given the relatively low species diversity in the alpine tundra, the loss of any species is projected to have a great impact on both species’ diversity and the ecosystem (Chapin III & Körner, 1995). This may cause the extinction of the species completely. The paper claims the greatest source of environmental change in the alpine regions will be due to the human impact in the coming decade. This claim is supported by recent research in the field where human activities have caused climate warming, leading to the reduction of the alpine tundra. Economic activities such as burning fossil fuels and land use changes cause climate warming and cause severe damage to the alpine tundra. Additionally, research showed people are less sensitive to changes within the ecosystem of alpine regions (Young and Chapin, Chap. 13, as cited in Chapin III & Körner, 1995). This intensifies the urgency for conservation efforts and highlights the need for increased awareness. Given the already small global proportion of the alpine tundra, its ongoing decline stresses the critical need for proactive measures to safeguard the fragile ecosystem.

Another paper during the same time highlighted views on the impact of global warming on alpine tundra. High latitude and altitude ecosystems, such as alpine tundra, demonstrate a heightened sensitivity to climate change (Pauli et al., 1996). Global warming resulted in the shifting of species in the mountain tops, and this will continue in the future. According to the paper, the upward shifting of high mountain plants has been noticeable since the 19th century and is continuing. This can be backed up as it was the century of and the start of the Industrial Revolution. The mass pollution started due to the mass burning of fossil fuels which contributed significantly to global warming (Ghosh, 2021). The earth’s average temperature has risen by 0.07°C every decade since 1880 (Ghosh, 2021). This can be connected to the damage to the alpine tundra that it faced globally due to the continuous increase in the earth’s temperature. Approximately 3% of the earth’s land is alpine tundra and of that, most of them are found in the Northern Hemisphere (Hu & Bliss, 2023). A few of the well-known highest mountains include Mount Everest in Nepal, K2 in Pakistan, and Shishapangma in Tibet. All of these mountain peaks are over 7,200 metres (23,622 ft) above sea level (Wikimedia, 2024)

Recent studies on snow cover show how important it is for the alpine ecosystem. Snow is an important driver of ecosystem processes in cold biomes. Hence it is crucial to understand it to value the alpine tundra. Snow cover influences ecosystems through both direct and indirect pathways, with its properties such as volume, water/ice content, timing and spatial distribution impacting soil temperatures, as well as the availability of light, water, and nutrients (Rixen et al., 2022).  The snowmelt timing in the alpine and subalpine in the Rocky Mountains is important to understand because the timing of the meltwater release from the winter snowpack can be a critical factor in shaping the composition of vegetation communities and the availability of freshwater (Rixen et al., 2022). Gathering global data focusing on snow’s impacts on tundra ecosystems can considerably improve the understanding of cold ecosystems in times of climate change. Few studies covered the changing duration of snow cover due to climate change and its effects on the alpine ecosystem (Rixen et al., 2022).

The importance of snow cover is further emphasized in the recent report by Goodman (2023). He points out that snow cover is crucial to the energy balance of the atmosphere and also for the plants, and animal species in the mountain areas as they are adapted to being in the Alps. The Alps provide almost 90% of the water to the lowland Europe. Snow cover is important for animal foraging, relief from climate stress, food coaching and nesting grounds. The loss of snowy habitats around the world has led to a decrease in population growth for some mountain animals. Reduced snow cover also impacts the soil conditions which impacts agricultural crops.

The Alps are a popular tourist destination, with around 120 million visitors coming every year for activities such as skiing, snowboarding, hiking and cycling. However, in recent years, the lack of winter snow has become a significant concern. In 2023, Alpine resorts had to bring in snow by helicopter and offer alternative entertainment, such as hiking with goats, due to the lack of snow (Goodman, 2023). Research shows that there has been an 8.4% decline per decade in seasonal snow cover in the Alps measured between November and May, between 1971 and 2019. Additionally, snow cover duration has dropped by 5.6% per decade. The duration of snow cover has been decreasing since the late 19th century. Figure 2 below shows periods of notably long and short snow cover duration in the past 600 years. Some of the longest periods include 1440-1460 and 1780-1800, while some of the shortest occurred in the low-snowy decades of 1940-1960 (Goodman, 2023). The declining trend of snow cover duration is evident since the start of the Industrial Revolution and towards the end of the Agricultural Revolution around early 1800s.

Figure 2 Snow cover duration from 1400 to 2018

Barredo et al. (2020), discuss three scenarios of the alpine tundra in 1.5, 2 and 3◦C warming levels. The current temperature of 1.5°C temperature is already causing a lot of problems in the alpine tundra and as the data indicates temperature will keep rising, the biome and its ecosystem will face much damage. Moving forward the temperature is expected to increase more which will almost make the alpine tundra non-existent (Barredo et al., 2020). Just to understand how massive this damage can be we can take the example of the alpine region of Europe from Barredo et al. (2020). For instance, at a 1.5◦C temperature, the Alps, Scandes and Pyrenees combined are expected to contract by approximately 44% to 48% compared to their current extent, which is equivalent to a reduction of around 37,000 km2 to 41,000 km2 out of 86,000 km2. This contraction is anticipated to escalate to over 57% or approximately 49,000 km2 at a 2◦C increase. Lastly, under a 3◦C warming, the projected loss in the three regions is expected to be 84% or around 72,000 km2.

Matching the paper of Barredo et al. (2020), a report by the European Commission concluded similar results (“Climate change and Alpine Tundra Loss,” n.d.). If climate warming reaches 3°C, the alpine tundra across Europe is projected to diminish by approximately 84% from its current state. These repercussions will disrupt the alpine ecosystems, biodiversity, and recreational activities like skiing. The reduction of alpine tundra will also significantly affect water resources during summer months, impacting water quality due to changes in sediment levels in rivers caused by shrinking alpine glaciers (“Climate Change and Alpine Tundra Loss,” n.d.). Additionally, the report emphasizes the potential harm to alpine species and the limitations imposed on winter sports.

Dumais et al. (2014) identified that the alpine tundra is considered one of the most vulnerable biomes to climate change. Warmer temperatures could potentially cause the advancement of treelines or the densification of shrub cover. This shift may lead to a reduction in the size of alpine tundra ecosystems, ultimately posing a threat to species confined to mountain peaks and potentially resulting in their local extinction (Dumais et al. 2014). The paper further discusses that the ecosystem becomes more complex in the higher alpine subzone. The paper mostly covers alpine vegetation and its ecosystem but more importantly, it pinpoints how complex the alpine ecosystem is and how the change in vegetation due to climate change contributes to the decline of overall alpine tundra. The table below, figure 3 was collected from the paper Barredo et al. (2020) shows the percentage of alpine tundra domain contraction (ATD) as the temperatures rise. The results also indicate that the treeline is projected to shift upward across mountain regions. This implies that as the alpine tundra domain shrinks the treeline moves upwards decreasing the alpine tundra in total. Pyrenees will also lose a hundred percent of their alpine region at temperature 3◦C.

Figure 3: Projected relative contraction of the alpine tundra domain (ATD)

Source: Barredo et al. (2020). Error bars created by excel for RCP4.5 and RCP8.5. Barredo et al. range was narrower

Testolin et al. (2020) highlight the crucial role of alpine ecosystems, which provide freshwater to over half of the world’s population and store up to 1% of the terrestrial carbon pool. The alpine tundra ecosystems, however, face significant threats from land use changes and anthropogenic climate impacts. According to the findings, Asia has the largest share of the global alpine area, accounting for nearly three-fourths (2.59 Mkm2), followed by South America (15%; 0.55 Mkm2), North America (9%; 0.32 Mkm2), and Europe (2%; 0.08 Mkm2). And Oceania and Africa collectively contribute only 1% to the global alpine area. The distribution of these regions is depicted in Figure 3, where red areas denote alpine regions on the world map.

Figure 4: Spatial distribution of alpine areas based on a 30 m spatial resolution map

Source: Global Alpine distribution (Testolin et al., 2020)

All these mentioned research papers pinpoint the alpine tundra’s global value. The biome’s global value is important to consider since it is on the verge of declining further. The Alpine tundra’s ecosystem has a crucial role to play globally for humans and species for access to fresh water and more. Using data collected from ESVD, the global value of the alpine tundra is calculated and discussed in the next section. However, due to a lack of data, the global value of the biome may be undervalued.

Data collected on the alpine tundra is from different research papers and reports. The Polar Alpine region’s price per ha per year was gathered in Int$ per ha per year from the Ecosystem Services Valuation database (ESVD) developed by Brander et al. (2023). The ESVD database contains 9,500 ESVD Int$ per ha per year values for 15 different biomes.  This research selected the biome Polar Alpine as a general category. Within this biome, there are 5 subcategories as shown in Table 1. Table 2 shows how many observations in total were used and from which continents and countries. Initially, 82 observations were extracted of which 71 of them had Int$/ha/year values and were used to calculate for the rest of the paper.

Table 1: 5 Subcatergories of the biome

Ice sheets, glaciers and perennial snowfields

Polar-alpine rocky outcrops

Polar tundra and desserts

Temperature alpine meadows and shrublands

Tropical alpine grasslands and herbfields

Table 2:  Continents location of the studies

Continents Countries All observations Observations with values

Africa Ethiopia, Kenya 5 5

Asia India, China 37 35

Europe Austria, Germany, Italy, Ireland, Macedonia, UK 27 22

North America Costa Rica, USA 13 9

Total 12 82 71

Table 3 below used data collected from the ESVD database and used the ES_1 (Ecosystem Services) and the international dollar value per hectare per year to calculate the average and median global value of the Polar Alpine biome also reflecting the Alpine tundra. Grouping Polar Alpine biomes and Alpine tundra together in valuation is done due to their ecological similarities, such as harsh climates and limited vegetation, leading to comparable ecosystem services. Also, data limitations in these remote areas often requires such an assumption and simplification. Both biomes face similar environmental threats and have limited economic uses, which could also contribute to a unified valuation approach. Also, the location of studies was not conducted in the Arctic, Greenland and Antarctica but in different continents as shown in Table 2. Despite this, differences between the biomes could warrant separate valuations if more detailed data were available. Future research will be needed.

The significant results were shown on food, climate regulation, maintenance of soil fertility and opportunities for recreation. Due to the varying results of the average, the median is used to ignore the outliers. Climate regulation also showed significant results on the median.

Table 3: ES_1 (Ecosystem Services)

ES_1	Average Int$/ha/year	Median Int$/ha/year	# of value
Food	570	<1	12
Water	41	25	5
Raw materials	103	2	12
Genetic resources	<1	<1	1
Ornamental resources	<1	<1	1
Medicinal resources	<1	<1	1
Climate regulation	862	1,017	6
Air quality regulation	229	3	7
Maintenance of soil fertility	440	1	5
Maintenance of genetic diversity	117	36	3
Maintenance of life cycles	<1	<1	1
Erosion prevention	76	37	3
Moderation of extreme events	145	145	2
Opportunities for recreation and tourism	363	47	5
Information for cognitive development	7	3	4
Existence, bequest values	86	<1	3
Total	3,038	1,317

The alpine tundra of Europe according to Barredo et al. (2020) is facing losses massively from the increase in temperature due to global warming. Using data from Barredo et al. (2020) research, Table 4 is calculated below. It shows as the temperatures increase how much value in ($) will be lost per hectare from the combined Alps, Scandes and Pyrenees. With the increase in temperature from 1.5◦C to 2◦C and 3◦C the area lost increases. The value of the loss in price ($) per hectare for average is calculated by taking the values of the total average from Table 3 and multiplying it by the site area from Table 4. The same method is used to calculate the median values of the price ($) per hectare. The current value of the biome was calculated using the value of area in Table 4 and multiplying it with the total value of average and median from Table 3. For example under 1◦C the average value was found to be US$ 26.13 billion per year in ecosystem services and the median value was found to be US$ 11.33 billion per year in ecosystem services. And if the temperature reaches 3◦C the value decreases massively to US$ 4.53 billion per year in ecosystem services.

Table 4: Loss of Alps, Scandes and Pyrenees as temperature rises to 1.5◦C, 2◦C and 3◦C.

Temperature anomaly	Area (millions of hectares)	Loss area in hectares (in millions of ha)	Reduction from current levels	Value ($)	Loss of value using the average price	Value($)	Loss of value using the median price
1◦C	8.6			26.13		11.33
1.5◦C	4.1	4.1	52%	12.46	12.3	5.39	5.33
2◦C	3.7	4.9	57%	11.24	14.7	4.87	6.37
3◦C	1.4	7.2	84%	4.53	21.6	1.84	9.36

Overall, the data was limited, and it mostly highlighted climate regulation. This makes sense because we have seen how most researchers tend to emphasize significantly on climate warming for the alpine tundra decline. There is more awareness now than before and hence more value is imposed on it. Other criteria like recreation and tourism also have higher averages, meaning people are willing to put more value on these as the damage to the biome increases as global warming increases. In the report by the European Commission, the mention of disruptions in recreational activities like skiing was discussed (“Climate change and Alpine Tundra Loss,” n.d.) which is a popular recreational activity in Europe.

Tundra soil does not have many of the nutrients that plants need to grow. Tundra biomes are mostly treeless and have some small shrubs, mosses, and grasses (“Tundra biome,” 2023). But it is interesting to observe that according to our calculations, the value of the maintenance of soil fertility has a high average. This can be linked to Goodman’s (2023) report where he mentions that snow cover impacts the soil conditions and hence agricultural crops. However, looking at the median makes more sense. It may be a similar case for the food criteria as well because the average is a high value, but the median is not. It may have more outliers, but more information and data are required to understand why they have significant averages.

One of the biggest setbacks of researching the Alpine tundra is there is little historical research on the biome. Pauli et al., (1996) also mentioned the lack of historical data that made the research on the alpine tundra limited. The alpine tundra is particularly vulnerable to global climate change, in addition to its relatively small geographical coverage worldwide. This limited geographical area contributes to the lack of research in the field, as fewer researchers are focusing on the alpine tundra (Wei & Wu, 2004).  Furthermore, Malanson et al. (2015) highlight another challenge in research, which is related to studies focusing on local patterns and dynamics of alpine tundra in relation to climate change. These studies revealed variability rather than a consistent general response, adding complexity to the study and understanding of the biome.

Even though the problem of global warming is the prime cause of the damage to the alpine tundra, it is important to understand that it started with different human activities. For example, in the report by Goodman (2023) he points out that tourists and recreational activities are hampered due to the decline in the biome, but in the 1900s hikers lacked proper hiking education and were responsible for about 30% of the destruction of the alpine tundra in some regions (Ketchledge, 1977, as cited in Allard, 2019). Trampling and soil erosion from a large number of hikers caused damage to the alpine tundra patches back then (Allard, 2019). What was destroyed back then and in addition to other human activities the biome is still decreasing. Humans are suffering from previously misused resources and the cycle will continue as they are continuously doing activities that it is increasing global temperature and damaging the biome. Education, awareness and proper initiative are important to tackle such a problem and break the cycle. Just because the alpine tundra is a small percentage of the world, less focus is given by researchers to the area leading to a lack of data. However, due to the biome’s crucial features, it should be given more importance especially when global warming is increasing at an increasing rate.

Furthermore, more precaution and research should be done for this biome as the damage that it already suffered is irreversible. If nothing is done now and it continues as it is the biome damage will get worse leading to ecosystem and societal collapse. Initially, it was believed that a 5°C rise over pre-industrial levels was needed to reach tipping points. However, new information suggests that some tipping points could be crossed with as little as 1-2°C of warming (Mulhern, 2020). Since we have already reached that temperature due to global warming, the tipping points have reached irreversible damage. Figure 5 below briefly shows the stages of reaching the irreversible equilibrium.

Figure 5 Created using https://miro.com/app/dashboard/

Tipping points are critical thresholds beyond which a slight disturbance can significantly alter a system’s state. Large-scale Earth components, called tipping elements, have tipping points that could be triggered by human activities. The alpine glacier is only a part of the global tipping points. Climate tipping elements either significantly contribute to the Earth system’s operation, significantly affect human welfare, or have great value as a unique feature of the Earth system (Armstrong McKay et al., 2022). Additionally, multiple climate tipping points are likely triggered as the Earth has already left a safe climate state beyond 1°C global warming. The probability of passing these tipping points increases significantly above 1.5°C, particularly in major ice sheets. Therefore, policies that lead to 2 to 3°C warming are not safe as they would likely trigger multiple climate tipping points (Armstrong McKay et al., 2022).

Figure 6:  Tipping point

Source: Retrived from https://climateataglance.com/climate-at-a-glance-tipping-point-1-5-degrees-celsius-warming/

Adding to that Armstrong McKay et al., (2022) further emphasized that with strong scientific evidence urgent action to mitigate climate change is required. The Paris Agreement goal of limiting warming to below 2°C is not safe as 1.5°C and above risks crossing multiple tipping points. Crossing some tipping points increases the likelihood of crossing other tipping points (Armstrong McKay et al., 2022).

Figure 7:  The Southern Alps of New Zealand, are past the tipping point due to climate change

Source: The Southern Alps of New Zealand. Retrived from https://www.courthousenews.com/new-zealand-glaciers-past-the-tipping-point-of-melting/

Another critical issue that requires more attention is the consequences of rising temperatures on people who rely on water sourced from the alpine tundra during the summer and spring seasons. If the biome persists in contracting, it will undoubtedly have a detrimental effect on those who heavily depend on mountaintop water. In a study from 2019, scientists researched the importance of the earth’s natural ‘water towers’ and found that about 1.9 billion people depend on these waters (Amos, 2019 & Immerzeel et al., 2019). The study found that over the next century, climate change will impact the water towers significantly which will impact the availability of drinking water, water for power, and water for agriculture. The loss of water will also impact the global food systems and biodiversity (Immerzeel et al., 2019). And because of this, almost more than 20% of the global population will suffer. The study further concluded that immediate action is necessary to mitigate the effects of this crisis and prevent dire water shortages. However, since the population is increasing the water demand is increasing and at the same time, the rise in global warming is also reducing the supply of water. This gap of disequilibrium is increasing with time and unless proper measures are taken the damage can be catastrophic.

One way to take initiative is to practice conservation and efficient water use. According to Immerzeel et al., (2019), irreversible changes in the buffering capacity of water towers are currently happening. To conserve these water towers, actions need to be taken at a global level to reduce global climate warming. Conservation efforts can include protecting the natural buffering capacity of mountain ranges in newly designated conservation areas, building reservoirs to increase this buffering capacity, and improving water-use efficiency to conserve water. Effectively managing scarce water resources can improve the quality of life, greater economic stability, and increase food security (Immerzeel et al., 2019).

Throughout the paper, we tried to showcase how significant the features of the alpine tundra are and how its decline can create numerous problems for different sectors like the mountain ecosystem, plants, animal species, and tourists. However, despite the great importance of the potential impact of higher temperatures in the high mountains, the understanding of the process is limited (Barredo et al., 2020). This limits the research on the biome as well.

While there is widespread agreement regarding the distribution and ecological characteristics of terrestrial biomes, the placement of alpine ecosystems within the global biogeographic framework remains unclear (Testolin et al. 2020). The paper points out that despite significant discrepancies in understanding alpine ecosystems, there is a lack of empirical understanding of their global ecological properties and relationships with terrestrial biomes. Current studies mainly focus on continental or regional scales, with global estimates relying on average regional tree line elevations or coarse resolution delineations of altitudinal belts. This knowledge gap hinders comparative analyses of alpine ecosystems despite their recognized similarities in dominant vegetation (Testolin et al. 2020). These may lead to a lack of proper data and a huge setback in evaluating the ecosystem of the alpine tundra. Furthermore, due to climate change and ice loss, most researchers focused on the rise of sea level and not enough on the loss of water resources (Amos, 2019). However, the loss of water is a global crisis, and more research should include and focus on it.

Another important setback is collecting proper data for evaluation. For example, Allard (2019) mentions in this paper that high-elevation locations’ climate norms are estimated using data from nearby monitoring stations situated at lower elevations than the mountain peaks hosting alpine tundra. This lack of directly measured data at the tundra sites generates uncertainty regarding the true climate norms in these areas. Hence hindering accurate assessment of the biome’s vulnerability to climate change.

For this paper, we were unable to find enough data for our calculation and finding the true value of the biome was limited. Considering all the critical purposes of the alpine tundra biome, it is highly undervalued. This research assumed that the Polar Alpine valuation also reflected the Alpine tundra valuation since there are no specific valuations of the Alpine tundra. This may not be valid although an average of $3,038  and a median of $1,317 is most likely an underestimation.

To conclude the greatest source of environmental change in the alpine regions is mostly due to the human impact. On top of that, warming temperatures disrupt the cold tundra biome, melting its underlying permafrost, and releasing greenhouse gases that further accelerate global warming (“Tundra biome,” 2023). Given its minimal global area, the biome’s importance is magnified, emphasizing the heightened necessity of its preservation. Strict policies, regulations and more awareness may be helpful to tackle this crisis on the alpine tundra. According to Wang et al. (2010) natural climatic conditions, permafrost environment, and human activities are the main causes of the change in the ecosystem of the alpine tundra.

Considering the known effects of warming on alpine tundra ecosystems and the inevitable global warming projected for the next century it is essential to grasp how future climate changes might affect these regions to guide conservation efforts. For example, recent species distribution models show that a 2-degree Celsius temperature rise could shrink the alpine tundra area in the European Alps to just a quarter of its current size (Allard, 2019). At present, the world is on track for approximately 2 to 3 degrees Celsius of global warming. Even if all the net-zero pledges and nationally determined contributions are put into action, the global temperature could decrease to just below 2 degrees Celsius. While this would reduce the risk of tipping points, it would still be hazardous because it might activate multiple climate tipping points (Armstrong McKay et al., 2022).

To precisely assess the value of the alpine ecosystem for future researchers, it is imperative to gather more precise data directly from the alpine region rather than from nearby monitoring stations. Obtaining more data is crucial for gaining a deeper understanding of the global significance of the alpine tundra and for accurately analyzing the rate of its degradation. As of now the research and data in the field is limited.

Allard, T. (2019). Potential impact of climate change on the distribution of alpine tundra in the Adirondack Mountains of New York. Scholars Archive. https://scholarsarchive.library.albany.edu/honorscollege_daes/18/?utm_source=scholarsarchive.library.albany.edu%2Fhonorscollege_daes%2F18&utm_medium=PDF&utm_campaign=PDFCoverPages

Amos, J. (2019, December 9). Climate change: 1.9 billion people rely on natural “water towers.” BBC News. https://www.bbc.com/news/science-environment-50707138

Armstrong McKay, D. I., Staal, A., Abrams, J. F., Winkelmann, R., Sakschewski, B., Loriani, S., Fetzer, I., Cornell, S. E., Rockström, J., & Lenton, T. M. (2022). Exceeding 1.5°C global warming could trigger multiple climate tipping points. Science, 377(6611). https://doi.org/10.1126/science.abn7950

Barredo, J. I., Mauri, A., & Caudullo, G. (2020). Impacts of Climate Change in European Mountains – Alpine Tundra Contraction under Future Warming Scenarios in Europe. Atmosphere, 11(7), 698. https://doi.org/10.3390/atmos11070698

Brander, L.M. de Groot, R, Guisado Goñi, V., van ‘t Hoff, V., Schägner, P., Solomonides, S., McVittie, A., Eppink, F., Sposato, M., Do, L., Ghermandi, A., and Sinclair, M. (2023). Ecosystem Services Valuation Database (ESVD). Foundation for Sustainable Development and Brander Environmental Economics.

 Climate change and Alpine Tundra Loss. European Commission. (n.d.). https://joint-research-centre.ec.europa.eu/system/files/2020-09/08_pesetaiv_alpine_tundra_habitat_loss_sc_august2020_en.pdf

Chapin III, F. S., & Körner, Ch. (1995). Patterns, Causes, Changes, and Consequences of Biodiversity in Arctic and Alpine Ecosystems. Ecological Studies, 113, 313–320. https://doi.org/10.1007/978-3-642-78966-3_22

Dumais, C., Ropars, P., Denis, M.-P., Dufour-Tremblay, G., & Boudreau, S. (2014). Are low altitude alpine tundra ecosystems under threat? A case study from the Parc National de la Gaspésie, Québec. Environmental Research Letters, 9(9), 094001. https://doi.org/10.1088/1748-9326/9/9/094001

Ghosh, I. (2021, February 9). Since 1850, these historical events have accelerated climate change. World Economic Forum. https://www.weforum.org/agenda/2021/02/global-warming-climate-change-historical-human-development-industrial-revolution/

 Goodman, J. (2023, February 15). Recent Alps snow cover decline “unprecedented” in past 600 years. Carbon Brief. https://www.carbonbrief.org/recent-alps-snow-cover-decline-unprecedented-in-past-600-years/

Hu, F. S., & Bliss, L. C. (2023, December 29). Tundra. Encyclopaedia Britannica. https://www.britannica.com/science/tundra

Immerzeel, W.W., Lutz, A.F., Andrade, M. et al. Importance and vulnerability of the world’s water towers. Nature 577, 364–369 (2020). https://doi.org/10.1038/s41586-019-1822-y

Malanson, G. P., Cheney, A. B., & Kinney, M. (2015). Climatic and geographic relations of Alpine Tundra Floras in western North America. Alpine Botany, 125, 21–29. https://doi.org/10.1007/s00035-014-0144-9

Mulhern, O. (2020, May 29). Tipping points in the earth system. Earth.Org. https://earth.org/data_visualization/tipping-points-in-the-earth-system/

Pauli, H., Gottfried, M., & Grabherr, G. (1996, September 1). Effects of Climate Change on Mountain Ecosystems – Upward Shifting of Alpine Plants. World Resource Review. https://www.osti.gov/biblio/379668

Rixen, C., Høye, T. T., Macek, P., Aerts, R., Alatalo, J. M., Anderson, J. T., Arnold, P. A., Barrio, I. C., Bjerke, J. W., Björkman, M. P., Blok, D., Blume-Werry, G., Boike, J., Bokhorst, S., Carbognani, M., Christiansen, C. T., Convey, P., Cooper, E. J., Cornelissen, J. H., … Zong, S. (2022). Winters are changing: Snow effects on Arctic and alpine tundra ecosystems. Arctic Science, 8(3), 572–608. https://doi.org/10.1139/as-2020-0058

T6 Polar/alpine (cryogenic) biome. Global ecosystem typology. (n.d.). https://global-ecosystems.org/explore/biomes/T6

Testolin, R., Attorre, F., & Jiménez‐Alfaro, B. (2020). Global distribution and Bioclimatic Characterization of Alpine biomes. Ecography, 43, 779–788. https://doi.org/10.1111/ecog.05012

 Tundra biome. National Geographic Society. (2023, October). https://education.nationalgeographic.org/resource/tundra-biome/#

Wang, G., Bai, W., Li, N., & Hu, H. (2010). Climate changes and its impact on tundra ecosystem in Qinghai-Tibet Plateau, China. Climatic Change, 106(3), 463–482. https://doi.org/10.1007/s10584-010-9952-0

Wei, J., & Wu, G. (2004, December). Vegetation biomass distribution characteristics of Alpine Tundra ecosystem in Changbai Mountains. Journal of Applied Ecology. https://pubmed.ncbi.nlm.nih.gov/15707302/

Wikimedia Foundation. (2024, March 29). List of highest mountains on Earth. Wikipedia. https://en.wikipedia.org/wiki/List_of_highest_mountains_on_Earth