Field Survey and Installing the Instruments

The Földgömb Atacama Climate Monitoring Expedition's  2012 field session followed its schedule and has been successfully completed. Major goal of the field work carried out on the dry plateau of Puna de Atacama with special focus on the Ojos del Salado had been launching a long-term measuring device-aided monitoring research:

  • We appointed representative locations suitable for measurements
  • Data of the first cycle of measurements (2012. February—2014. February) will serve as a base for the monitoring. Therefore, we placed temperature measuring instruments at each characteristic climate-morphological and elevation zones of the high mountain environment.
  • Our major goal is to analyze processes of the permafrost's active layers, we placed temperature measuring data loggers—reading data every 30 minutes—into the regolith (volcanic pyroclast) at several levels and depths:  
    • at 4200 m, at 10 and 35 cm depths,
    • at 5260 m, at 10, 35 and 60 cm depths,
    • at 5830 m, at 10, 35 and 60 cm depths,
    • at 6750 m, at 10 and 17 cm depths,
    • at 6893 m, on the surface at two locations, at 10 cm depth (+ humidity measuring device on the surface).
  • Having installed these devices, we launched  the highest elevation permafrost monitoring on Earth.
  • The major monitoring locations are the northern slopes of Ojos del Salado, and we also installed data loggers into the polygonal ground of the stony desert next to Laguna Negro Francisco at 4200 m.
  • Along with instrument aided measurements we also studied the occurrence of alpine periglacial processes and their subsurface positions.

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The First Measurements Expected Results

  • Complete dataset regarding the second half of the 2011/12 melt season (summer), the entire melt season of 2012/13 and the first half of the 2013/14 melt season. (In case of an exceptionally strong melt season in 2014 we plan to place our data loggers deeper into the soil.)
  • Exploring the local freeze-thaw cycles
  • Discovering the lengths of melt season(s).
  • Detailed monitoring of the active layer's warming and refreezing; determining the active layers temperature distribution.
  • Defining the active layer's (the uppermost, melting layer of the ground) maximum thickness at different elevations.
  • Creating a database for long-term permafrost degradation analyses, and for monitoring the pyroclast's moist content and meltwater deriving from permafrost.

 

Analyzing aeolian activity

The study area is the highest desert and stoney tundra on Earth. Hence, the wind is a major landforming agent in this environment. Results of 2012 field research:

  • Landforms of the desert and the stoney tundra are mostly formed by winds between 4600 m to 6300 m a.s.l.
  • Megaripples compete in size with the Earth's largest known megaripples  (found on the Puna's Argentinean side). These forms occur up to 5500 m a.s.l. in the area of Ojos del Salado, as well.
  • Their material is mostly light-weight pyroclastic material and ignimbrite with high pumice content.
  • Determining layers and structure of megaripples.
  • Between 5200-5500 m extreme winds accumulate 3-4 cm large, heavy andesite  particles on the forms' windward sides and ridges - making ripples inactive.  
  • Sampling particles for determining launch velocity and laboratory analyses of large particle movements.
  • Above 5200 m winds erode all the outcropping rocks; westward sides are extremely eroded.
  • On the slopes of older lavaflows large-grain lee-side dunes are created.
  • Erosional cuts on the coarse sediment-covered regolith surface are cleared away (filled) within 1 or 2 years by wind transported large-grain sediments.

 

The Earth's Highest Lakes

  • Two shallow pits that are temporary lake beds were filled completely with snow in 2012. The one at 6380 m is a lake bed we already discovered in 2010, but the other pit at 6450 m is a new discovery.
  • These basins are characterized by 100-200 m diameters and may contain water for a few weeks at the end of the melt season. (A great amount of snow needs to be melt in a short period of time and daily temperatures need to remain steadily above zero for the temporary lake formation.) The regolith's permafrost content buffers and also hinders the escape of meltwaters.  
  • The location of the newly discovered lake bed is in a parasite crater containing fumaroles at 6450 m. At the time of our observations water flowed onto the snow and the snow became water-saturated.

 

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