View from atop a glacier looking toward mountains on the horizon
A view of the Andes in south central Chile is seen from the main glacier covering the Nevados de Chillán volcanic complex. Credit: Alfonso Fernández

Glaciers have long been thought of as static, picturesque totems or as changeless coverings over permanently frozen landscapes, particularly among societies distant from mountains and the poles. However, as traditional mountain cultures with firsthand experience have long known and treasured—and as glaciologists, hydrologists, and climate scientists have deciphered and communicated—glaciers are by no means static. Rather, they are dynamic landscape agents and unmistakable indicators of rapid environmental transformation [Gagné et al., 2014]. With widespread media coverage of anthropogenic climate change and the realization that glaciers are endangered species [Carey, 2007], popular perceptions are gradually changing, and scientists, grassroots movements, and policymakers are increasingly committing to developing legal protections for glaciers.

In 2006, legislative efforts to enact a glacier protection law in Chile started as a result of increasing concerns about how mining activities were endangering small glaciers in the north of the country [Herrera Perez and Segovia, 2019]. Around the same time, other initiatives affecting glacierized basins, such as the HidroAysén hydroelectric project, helped to galvanize local and national activists, who demanded stronger environmental actions from the government. With the country facing significant challenges associated with a long drought affecting its most populated regions, environmentally focused legislation has become a main priority for many Chileans after the populace overwhelmingly requested a new constitution. As of early 2021, the latest initiative related to glaciers, called the “Ley sobre protección de glaciares” (law for glacier protection), is still in discussion in the Senate chamber. Despite the law’s admirable aims, in its current form it includes some flaws that, if passed, will undermine its effectiveness.

Chile’s Crucial Cryosphere

Stretching roughly 4,300 kilometers from Cape Horn in the south to its northern border while spanning only about 180 kilometers on average between the Andes and the Pacific Ocean, Chile contains most of the ice and snow cover in the Southern Hemisphere outside the polar regions. It also hosts a significant yet little-studied periglacial landscape characterized by permafrost features, including soils and rock glaciers, among others (Figure 1). Glaciers, snow, and permafrost are found along the Chilean Andes and across several climatic regimes, from nearly tropical to subantarctic, epitomizing the wide range of the environmental conditions where these water reservoirs can grow and wane.

Map of glaciers around the world with inset of Chile showing potential locations of permafrost
Fig. 1. This world map shows the locations of glaciers around the world according to the Randolph Glacier Inventory. Chile’s borders are outlined in red. The inset map of Chile shows potential locations of permafrost as indicated by the Global Permafrost Zonation Index Map.
Waterfalls pouring from a distant glacier run down a valley toward a mountain lake.
Waterfalls pour from an outlet glacier in Queulat National Park in Chilean Patagonia. Credit: Alfonso Fernández

Chile’s cold environments are part of the essence of the country, and socioeconomic development here is ineradicably linked to cryosphere dynamics. Agriculture, mining, drinking water provision, hydroelectricity, tourism, and ecosystem services depend, in one way or another, upon the presence of snow and ice. In the south, for example, the majestic glacierized Patagonian landscape attracts visitors from all over the world. In the semiarid north and center of the country, large agricultural areas, including Chile’s world-renowned wine-producing regions, are watered largely by mountain streams nourished by ice and snow melt. In a sense, anyone enjoying a Chilean Carménère is likely tasting drops of the Chilean cryosphere.

A legal framework that considers the latest technical and theoretical understanding of Chile’s cold environments is essential for effective regulation and for maintaining the cultural and socioeconomic value these environments provide. Members—including ourselves—of the Sociedad Chilena de la Criósfera, the only scientific society in Chile dedicated to studying the country’s cryosphere, and other geoscientists have appealed to the National Congress of Chile and the public to provide support and advice to develop scientifically sound and accurate legislation. However, we are increasingly concerned about the effectiveness of the glacier protection law because current iterations under discussion in the congress include misleading concepts and criteria.

Some Limitations of the Proposed Law

At the most basic level, we are alarmed by how proposed legislation uses “cryosphere” and “glaciers” synonymously.

At the most basic level, we are alarmed by how these proposals use “cryosphere” and “glaciers” synonymously. The proposed legislation covers glaciers and permafrost, so a more accurate framework would entail protection of the entire cryosphere. However, there are more profound concerns that may become hard to correct once the law is enacted. Among others, these concerns include unfeasible definitions of what a glacier is, poor understanding of the relationship between glacial and periglacial environments, and impacts of the proposed legislation on key infrastructure.

Fundamentally, a glacier is a body of ice massive enough to flow under its own weight, a characteristic that sets it apart from perennial snowfields or smaller patches of snow and ice. Combining understanding from Glen’s flow law, a fundamental glaciological tenet that relates ice flow velocity with slope and thickness [Cuffey and Paterson, 2010], with well-established relationships between glacier surface area and volume [Bahr et al., 1997] offers guidance on the minimum size of an ice patch that can be considered a glacier.

A panoramic view of Universidad Glacier in central Chile
A panoramic view of Universidad Glacier in central Chile. Credit: Alfonso Fernández

During congressional discussions, overly simplistic definitions of glaciers based on flow properties and debris cover have been contrasted with definitions considering more operative yet technically contestable criteria, such as a minimum surface area threshold to be used for mapping and protection purposes under the law. Some proposals by members of congress have argued that this minimum limit should be as small as 0.1 hectare (1,000 square meters). This threshold is much stricter than what is normally applied in the scientific literature, which suggests instead that a surface area of 1 hectare (about the size of a soccer field) may be a more reasonable threshold to use in mapping glacial inventories [Paul et al., 2009; Leigh et al., 2019].

A 0.1-hectare threshold would make it possible to misinterpret ephemeral firn or snow patches as bodies of glacier ice. Under a wide range of realistic glacier surface slopes, the flow law predicts surface velocities well within the uncertainty range of modern measurement techniques like high-precision GPS for average ice thicknesses (about 4 meters) corresponding to the 0.1-hectare threshold. Also, energy and mass balance research shows that Chilean glaciers can melt at rates in excess of 15 meters per year [e.g., Kinnard et al., 2018]. Thus, plausible rates of 4 meters per year result in total melt out of a 0.1-hectare surficial frozen water body within a year or so, further supporting the idea that such small bodies should not be cataloged as glaciers in inventories.

The current proposal and ongoing debate are flawed because they do not consider the hydrological role of permafrost and periglacial areas.

Within the law, permafrost and periglacial environments are key elements to be protected, and rightly so. There is plenty of science suggesting that many areas experiencing water stress are covered by sediments and soils that may contain either perennial or seasonal ice (Figure 1) [Ruiz Pereira et al., 2021]. These environments are demarcated on the basis of morphological features, such as the presence of frozen ground, as well as climatic thresholds, particularly with respect to the elevation of the zero-degree isotherm (above which the air temperature is always below 0°C). Although these criteria are in line with established understanding of the conditions that sustain permafrost and rock glaciers [Dobinski, 2011], the current proposal and ongoing debate are flawed nonetheless because they do not consider the hydrological role of permafrost and periglacial areas. In high-elevation regions, including large areas of the Chilean Andes, water storage and drainage are sensitive to permafrost, rock glacier, and glacial changes. Therefore, overlooking this role is inexplicable, especially considering that the first article in the law explicitly indicates that the main reason for preserving glaciers, permafrost, and periglacial areas is their critical value as strategic water reservoirs.

How Geoscientists Can Contribute

We understand some of the considerations and debates surrounding the glacier protection law in Chile—for example, over the minimum surface area threshold—on the grounds that lawmakers are hoping to forestall future legal battles over its interpretation and application. Such battles have occurred in Argentina following implementation of a law similarly intended to preserve that country’s cryosphere. There, conflicting civil and private judicial challenges associated with the use of a 1-hectare threshold in the official glacier inventory have been launched, with the mining sector contending the threshold was too restrictive and others saying it did not protect enough area. These challenges led to the indictment of the chief scientist in charge of compiling the inventory for allegedly failing to uphold the country’s glacier protection law when he adopted the 1-hectare threshold, ironically punishing one of the few people who fought to use the most reliable scientific evidence in cryosphere protections.

Four people stand on snowy ground in a high mountain valley.
Glaciologists traverse a valley glacier in central Chile to deploy sensors. Credit: Alfonso Fernández

As scientists, we know that enacting a law will not end conflicts over how to govern Chile’s glaciers and cryospheric environments. We want to build bridges between citizens and the government to inform expectations of the law on all sides and to provide clear and accurate information for policymaking. As Isaac Asimov said, “The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.” We echo this and believe there is a unique opportunity to fine-tune Chile’s policymaking by implementing dynamic and updatable features in the country’s cryosphere protection law.

For example, the law should establish panels of academic experts, citizens, and public officers tasked with regularly updating operative definitions used in the legislation and with reviewing the latest technical developments (e.g., improvements in methods for glacier inventorying and monitoring). This approach could facilitate assessment of potential effects of activities, such as tourism and/or the development of water management infrastructure, within glacierized and periglacial areas.

This practice is not new: Expert panels often support policy—related to the ongoing COVID-19 pandemic and to fisheries management, for instance—by providing guidance about implications of the latest research and by proposing and evaluating metrics. In the case of glaciers, such an advisory group could, for instance, study criteria for mapping small glaciers [Leigh et al., 2019]. Considering the substantial seasonal and interannual dynamics and variation of glaciers, this kind of approach can help harmonize preservation and management.

The scale and preeminence of Chile’s glacial and periglacial landscapes argue for the nation’s responsibility and opportunity to lead the world in cryosphere protection.

Today we see with great hope that Chile is finally awakening to the value and fragility of its grandiose glacierized Andean landscapes, rather than turning its back, as celebrated French glaciologist Louis Lliboutry lamented during his 20th-century journeys through the Andes [Lliboutry, 1956]. The scale and preeminence of Chile’s glacial and periglacial landscapes argue for the nation’s responsibility and opportunity to lead the world in cryosphere protection. Thus, governmental actions regarding protection should serve as frameworks for other nations facing impacts of climate change in mountainous areas.

In our view, the current version of the proposed law regrettably suffers from uncertainties and omissions that could sow further conflict instead of the solutions expected by Chile’s public. We assert that it can be improved significantly if the country’s well-trained scientific community is consulted. This community is eager to cooperate in developing accurate regulation that can serve as a milestone for the rest of the world. We hope that the congress heeds our offer before passing misguided legislation.


Bahr, D. B., M. F. Meier, and S. D. Peckham (1997), The physical basis of glacier volume-area scaling, J. Geophys. Res., 102, 20,355–20,362,

Carey, M. (2007), The history of ice: How glaciers became an endangered species, Environ. Hist., 12, 497–527,

Cuffey, K. M., and W. S. B. Paterson (2010), The Physics of Glaciers, Butterwoth-Heinemann, Burlington, Mass.

Dobinski, W. (2011), Permafrost, Earth Sci. Rev., 108, 158–169,

Gagné, K., M. B. Rasmussen, and B. Orlove (2014), Glaciers and society: Attributions, perceptions, and valuations, Wiley Interdiscip. Rev. Clim. Change, 5, 793–808,

Herrera Perez, J., and A. Segovia (2019), Ley de Protección de Glaciares: El devenir de un conflicto socioambiental, Invest. Geogr., 58, 118-134,

Kinnard, C., et al. (2018), Mass balance and meteorological conditions at Universidad Glacier, central Chile, in Andean Hydrology, pp. 102–123, Taylor and Francis, Boca Raton, Fla.,

Leigh, J. R., et al. (2019), Identifying and mapping very small (<0.5 km2) mountain glaciers on coarse to high-resolution imagery, J. Glaciol., 65, 873–888,

Lliboutry, L. (1956), Nieves y glaciares de Chile: Fundamentos de Glaciología, Ed. de la Univ. de Chile, Santiago.

Paul, F., et al. (2009), Recommendations for the compilation of glacier inventory data from digital sources, Ann. Glaciol., 50, 119–126,

Ruiz Pereira, S., et al. (2021), Permafrost evolution in a mountain catchment near Santiago de Chile, J. South Am. Earth Sci., 109, 103293,

Author Information

Alfonso Fernández (, Mountain GeoScience Group, Departamento de Geografía, Universidad de Concepción, Concepción, Chile; Shelley MacDonell, Centro de Estudios Avanzados en Zonas Áridas, La Serena, Chile; Marcelo Somos-Valenzuela, Centro Butamallín: Investigación en Cambio Global, Universidad de la Frontera, Temuco, Chile; and Álvaro González-Reyes, Centro de Observación de la Tierra Hémera, Universidad Mayor, Santiago, Chile


Fernández, A., S. MacDonell, M. Somos-Valenzuela, and Á. González-Reyes (2021), Chile’s glacier protection law needs grounding in sound science, Eos, 102, Published on 06 July 2021.

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