Sporadic permafrost at unusually low latitude. Borehole temperatures show it's relict from the last glacial maximum, now thawing at 10cm per decade and releasing trapped organic carbon.
A Pleistocene hangover
In the high valleys of the Tian Shan mountains of southeastern Kazakhstan, patches of ground remain frozen year-round. This is permafrost, but its existence here is unusual. Located at a latitude of around 43° North—similar to Florence, Italy—this frozen earth is a relict from a much colder time. Scientific analysis shows this ground has been continuously frozen since the Last Glacial Maximum, a period of peak glaciation that ended more than 20,000 years ago.
This specific type of frozen ground is known as sporadic permafrost, occurring in isolated patches where local conditions are favorable. In the Koksu River valley, these patches often survive on north-facing slopes or are insulated by a thick layer of coarse, blocky debris that shields the ground from summer heat. While permafrost is common in the Arctic, its presence at these lower latitudes records the climate of the Pleistocene. The mountains of the Tian Shan are primarily composed of Paleozoic crystalline and sedimentary rocks, and the basins between them are filled with younger sediments where this relict permafrost is found. Researchers have identified the lower boundary for this type of permafrost in the Tian Shan to be at an altitude of 2800–3000 meters.
A slow and steady thaw
This ancient permafrost is now warming. Geothermal observations from boreholes drilled deep into the ground show a trend. Over the last 30 years, permafrost temperatures in the Tian Shan have increased by 0.3°C to 0.6°C. This warming causes the active layer—the upper layer of soil that thaws in summer and refreezes in winter—to deepen. In this region, the average thickness of the active layer has increased by 23% since the early 1970s.
The rate of thaw is steady, with the boundary between the active layer and the permafrost proper descending at about 10 centimeters per decade. This process is irreversible on human timescales. As the ground warms, it awakens microbial life that has been dormant for millennia. These microbes begin to decompose the vast stores of organic carbon locked within the frozen soil. This material consists of ancient plant roots, dead animals, and other biomass that never had a chance to decay in the frozen conditions. The decomposition releases greenhouse gases, primarily carbon dioxide and, in wetter conditions, methane. Globally, permafrost is estimated to hold about 1,500 billion tonnes of organic carbon, nearly twice the amount currently in the atmosphere. The thawing of even this mid-latitude permafrost contributes to a global climate feedback loop.
💡Fun Facts
The latitude of this permafrost is comparable to that of central Spain or Boston, USA, regions not typically associated with frozen ground.
The permafrost here is a "relict," meaning it formed under past, colder climate conditions and has survived to the present day.
The organic matter being released was frozen during the Pleistocene epoch, when woolly mammoths roamed Eurasia.
Scientists use temperature loggers inside boreholes, some over 30 meters deep, to monitor the slow warming trend deep within the ground.
This is a remote, natural scientific area accessible at all times, though conditions are dictated by weather and season.
Admission
Free.
Accessibility
The site is in a high-altitude, mountainous region. Access requires off-road vehicles and considerable hiking over difficult terrain. It is not accessible for those with mobility issues.
Koksu River valley permafrostAlmaty Region, Kazakhstan