Map of Peru's High Andes Vanishing Glaciers and Ice Peaks

Peru — Vanishing & Former Glaciers (quick reference)

Types of Glaciers that used to be common (and what remains)

Peru still hosts many of the world’s tropical glaciers, but total glacier area has dropped sharply since the mid-20th century. Small cirque/niche glaciers have largely disappeared; larger valley glaciers remain mainly in the Cordillera Blanca and around the Quelccaya Ice Cap (Cordillera Vilcanota), yet are thinning and retreating fast.

Cirque & niche glaciers (mostly former): Once widespread above ~5,000 m; now widely deglaciated or reduced to stagnant, debris-covered ice.
Valley glaciers (remain, retreating): Multi-km tongues in U-shaped valleys of the Blanca/Vilcanota; active but rapidly thinning, with growing proglacial lakes.
Plateau ice fields (diminishing): Quelccaya remains the largest tropical ice mass; outlet tongues like Qori Kalis have pulled back strongly.

How to Recognize Former Glacier Limits (what to look for)

Moraines: Paired lateral ridges and arcuate terminal walls of bouldery till; kettles and hummocky terrain on their toes.
Trimlines & color breaks: Sharp changes in lichen/varnish and vegetation height along valley walls marking past ice surfaces.
Polished/striated bedrock: Streamlined roches moutonnées and parallel grooves pointing down-ice.
Overdeepenings & tarns: New/expanding lakes behind moraines or in bedrock basins below retreating tongues.
Meltwater pathways: Fresh fans, braided channels, and ice-contact terraces across recently deglaciated forefields.

Former Glacier Structure (now diminished)

Accumulation vs. ablation: Rising equilibrium-line altitudes erased the net-gain zone on small/medium glaciers; tongues stagnated and wasted under debris cover.
Lake-terminating dynamics: Proglacial lakes enhance calving and subaqueous melt, accelerating retreat where deep water reaches the snout (e.g., Qori Kalis at Quelccaya).

Retreat Timeline (very brief)

Net losses since the Little Ice Age accelerated through the 20th century and again after ~2000. The steepest declines are in the central and southern ranges; the Cordillera Blanca and Vilcanota still host the largest remaining ice but are rapidly shrinking.

What Changes Without Reliable Dry-Season Runoff?

Hydrology: Earlier melt peaks and lower late-dry-season baseflows; rapid growth of proglacial lakes; shifting channels and sediment loads.
Hazards: Moraine-dammed lake outburst risk (e.g., Palcacocha) from avalanches/rockfall into lakes; ongoing monitoring and engineering works in key basins.
Ecosystems: Cold-water habitats contract; upslope shifts in vegetation; localized acidification where freshly exposed sulfides weather.
People & economy: Tighter late-season water windows for irrigation, cities, and hydropower; need for storage, efficiency, and demand management.
Tourism & culture: Sites like Pastoruri pivot to “climate-change route” interpretation as glacier surfaces vanish or become unsafe.

Key Areas & Named Glaciers — short history notes (edit freely)

Quelccaya Ice Cap (Vilcanota): Largest tropical ice mass; margins retreating on all sides. Outlet Qori Kalis formed a growing proglacial lake and pulled back rapidly since the 1990s.
Cordillera Blanca (e.g., Artesonraju, Alpamayo, Palcaraju): Strong mass losses since late 20th c.; dozens of new/expanded lakes. Repeated hazard studies for downstream towns (Palcacocha).
Huascarán / Huandoy basins: Long valley glaciers fragmented and thinned; classic moraines and young lakes provide “then/now” mapping sites.
Pastoruri (southern Blanca): Severely diminished; managed as a climate-change interpretive destination rather than a glacier-tour venue.
Huaytapallana (central Andes): Rapid areal losses; emblematic dry-season water-supply stress near Huancayo.
Coropuna (southern Peru): Volcanic ice cap with multi-decadal retreat; shrinking accumulation area and new lakelets around decapitated tongues.

Peru Glacier Database Field Descriptions

PHOTO_YEAR
Description: The 4-digit year of the photograph used for measurements of Peru glacier parameters. Note: If more than one photograph were used, the most relevant year is recorded here; and the others used are recorded in the REMARKS field. In general, the Peru glaciers outlines; and hence, the values for area and length; were determined from Peru aerial photographs, so we recommend using the PHOTO_YEAR for glacier area values.
No Data Value: Null
Example: 1976

MAX_ELEV
Description: Maximum elevation of the highest point of the Peru glacier in meters above sea level, up to 4 digits.
No Data Value: Null
Example: 3962

MEAN_ELEV
Description: The mean elevation is the altitude of the contour line, in meters above sea level, that halves the area of the glacier, up to 4 digits.
No Data Value: Null
Example: 3170

MIN_ELEV
Description: The minimum elevation of the lowest point of the glacier in meters above sea level, up to 4 digits.
No Data Value: Null
Example: 1590

FORM
0 Miscellaneous Any type not listed below.
1 Compound Basins Two or more individual valley glaciers issuing from tributary valleys and coalescing.
2 Compound Basin Two or more individual accumulation basins feeding one glacier system.
3 Simple Basin Single accumulation area.
4 Cirque Occupies a separate, rounded, steep-walled recess which has formed on a mountain side.
5 Niche Small glacier in a V-shaped gully or depression on a mountain slope; generally more common than genetically further-developed cirque glacier.
6 Crater Occurring in extinct or dormant volcanic craters.
7 Ice Apron Irregular, usually thin ice mass which adheres to mountain slopes or ridges.
8 Group A number of similar ice masses occurring in close proximity to one another but are too small to be assessed individually.
9 Remnant Inactive, usually small ice masses left by a receding Peru glacier.

FRONT_PROF:
0 Miscellaneous Any type not listed below.
1 Piedmont Ice field formed on a lowland area by lateral expansion of one or coalescence of several glaciers.
2 Expanded Foot Lobe or fan formed where the lower portion of the glacier leaves the confining wall of a valley and extends on to a less restricted and more level surface.
3 Lobed Part of an ice sheet or ice cap, disqualified as an outlet glacier.
4 Calving Terminus of a glacier sufficiently extending into sea or lake water to produce icebergs; includes- for this inventory- dry land ice calving which would be recognizable from the "lowest glacier elevation."
5 Confluent Coalescing, non-contributing.
6 Irregular, mainly clean ice (mountain or valley glaciers).
7 Irregular, mainly debris-covered (mountain or valley glaciers).
8 Single lobe, mainly clean ice (mountain or valley glaciers).
9 Single lobe, mainly debris-covered (mountain or valley glaciers).

TONGUE_ACT: 0 Uncertain
1 Marked retreat
2 Slight retreat
3 Stationary
4 Slight advance
5 Marked advance
6 Possible surge
7 Known surge
8 Oscillating

TOTAL_AREA:
The total area of the glacier in a horizontal projection in square kilometers.

AREA_ACY:
Area Accuracy Ratings
Rating Accuracy (%)
1 0 - 5
2 5 - 10
3 10 - 15
4 15 - 30
5 > 30

AREA_IN_ST:
The total area of the Peru glacier that resides in the political state concerned in a horizontal projection in square kilometers.

AREA_EXP:
The area of the exposed ice of the glacier in a horizontal projection in square kilometers.

MEAN_WIDTH:
The mean width of the Peru glacier in a horizontal projection in kilometers.

MEAN_LENGT:
Mean length of the Peru glacier in a horizontal projection in kilometers.

MAX_LENGTH:
Maximum length of the Peru glacier in kilometers measured along the most important flowline in a horizontal projection.

MAX_LEN_EX:
Maximum length, in kilometers, of the exposed ice of the glacier in a horizontal projection.

MAX_LEN_AB:
Maximum length, in kilometers, of the ablation area of the Peru glacier in a horizontal projection.

Overview of Retreating Glaciers in Peru