Climate

The Project is located east of the Andes between the lake General Carrera and the Northern ice field.

The valley has continental trans-andean temperate cold boreal climate, with cold boreal forest and progressive change into shrub steppes.

The valley is the coldest in the region. It has it’s own microclimate.

The moderating effect of the lake General Carrera shall be taken into account: the valley has less extreme weather than places further away from the lake, for example cities of Coyhaique and Balmaceda.


The following was collected from climate literature, but data is changing due to climate change:

This area differs from the others because it is protected by the mountain range of the Andes, which allows a significant decrease in rainfall compared to the sector of archipelagos on the same latitude.

Roughly two parallel areas are recognized in the region, extending from north to south, with completely different climates as to their biological effects: the eastern or trans-Andean area has a more arid climate with significant annual temperature fluctuations, under strong influence of neighboring bioclimates of Argentina, especially in terms of increasing some continental trends. The region is a transition zone between the two areas, experiencing even faintest Mediterranean influences.

In this sector the weather is dominated by two factors. The first, and there is no equivalent part in the world in which this factor plays such a crucial role, is the very strong and highly predominant west wind while the second one are the Andes and their ice fields.

Wind: The area has strong west winds year-round without any major positive or negative deviation, i.e. they are nearly evenly distributed over the different seasons. The annual mean windspeed is approximately 12 m/s. The monthly means never drop below 8 m/s, while every single month the maximum windspeed exceeds 30 m/s. Therefore, this region is called the "roaring forties", although these terms were minted for the oceanic environment.


Due to this pronounced dominance of west winds, 75%, local wind phenomena like sea or valley winds are most of the time overshadowed. These year-round strong winds put the vegetation in Patagonia under stress due to enhanced evapotranspiration. In contrast to the precipitation there is no pronounced difference in the wind regime due to the Andes.

Rainfall: Rainfall is lower than in other climates as the sector is protected by the Andes.

There is no predominant depression in west-east direction in this part of the Andes, the precipitation regime is very strongly divided in Patagonia: a western part and an eastern part from the Andes to the Atlantic coast with very little precipitation, reaching 500 mm/a at most.

If following a transect through Patagonia from west to east, it can be observed that over a distance of only 60 km from the main cordillera to the eastern foreland the annual means drop from 5.000 mm/a at the low end to 500 mm/a at the most. Along this very short distance the precipitation regime changes therefore from fully humid to semi-arid. In accordance to this strong gradient the change in vegetation cover from Magellanic Rainforest to Patagonian steppe is observed in merely 25 km.

For all of Patagonia the cloud cover is extraordinary high, with a mean of 5/8.

Temperatures: Temperatures are generally low, January having the highest and July the lowest temperatures. In winter, temperatures normally fall below 0 ° C, with frequent snowfall. In summer, high temperatures attributed to the effect of continentality, are attenuated by strong winds blowing from the mountains. Average annual temperatures vary around 9 ° C, with an increase of temperature range. The highest thermal fluctuation registered between the hottest and the coldest month is of about 12 º C, and average temperatures are 1 to 2 ° C lower those of the the climate in the western part of the region.

In the region the cold is a strong limiting factor, reducing the warm season to 4-5 and sometimes just to 2-3 months only.

The influence of the cold pacific air masses and the almost ubiquitous cloud cover leads to a rather small mean daily and yearly temperature amplitude of around 5° C. The daily and yearly variations of the mean and absolute extreme temperatures get more pronounced to the east. This is due to the distance to the Pacific and therefore a more continental component. This leads to a better thermal situation for the eastern part in the summertime, while in the wintertime this is reversed.

While the Antarctic sea-ice reaches its maximum extent in winter, it slowly recedes in spring and quickly extends in fall due to diminishing daylight. This leads to the late arrival of summer and its early termination. The main influence of the Antarctic continent is that to the west of Patagonia, over the Pacific, cyclones are built, which accommodate the cold air masses of Antarctica and drive them towards the Andes. These cold air masses get slightly warmer while being transported over the Pacific and are responsible for the Antarctic influence on Patagonia. During these situations however, they then have a strong influence on eastern Patagonia due to the absence of heating over the Pacific.

This leads to the situation that frost can occur east of the Andes at any time in the year and cause critical damage to the vegetation cover. There are only small seasonal changes in the temperature regime in contrast to the same latitude in the northern hemisphere, but "all the seasons can be observed in a single day” which is absolutely true in the Project.

The Project registered:


The strongest wind was 71 m/s or 200 km/h- just a gust.

It is not unusual to have sustained winds of 20 -25 m/s or 80 km/h.


There were extreme rain events in August 2010 and again in May 2011, resulting in with floods and landslides.


Links to weather conditions in nearest towns:

Puerto Rio Tranquilo

Puerto Guadal

landslide in valley Leones

landslide in the valley 2011

Please note that weather sites usually underestimate the influence of the Northern Patagonian ice field on the valley and forecast more precipitations and less wind than in reality.

December 2018

Contribution of the region to climate change:

  1. Massive deforestation by fire = drastic reduction in greenhouse gases absorption;

  2. Clearing fires of last century = a region-wide increase of emissions. Fires accelerate global warming because of

   the enormous quantities of carbon dioxide released in the atmosphere;

  1. Rapid development of tourism = actual important increase in CO2 emissions.


Climate change, quite visible in the valley and region, is being taken into account in order to anticipate pressure on the reforestation Project.  For its development the Project is studying ancient climate, as by 2030 the global climate will the climate of the Earth will look like that of three million years ago: Le climat de la Terre va ressembler à celui d'il y a trois millions d'années.pdf


The hole in the ozone layer over the region affects the climate of the region more than do the greenhouse gases, this phenomenon might persist until 2045-2060.