Environmental records from temperate glacier ice on Nevado Coropuna saddle, southern Peru

Abstract

Abstract. We investigated past climate variability and the zonal short and long-range transport of air masses in tropical South America using chemical, isotopic and palynological signals from a 42 m-long ice core recovered in 2003 from the saddle of the Nevado Coropuna, southern Peru (72 • 39 W; 15 • 32 S; 6080 m a.s.l.). We found that precipitation at this site depends mainly on the easterly circulation of air masses originated from the tropical Atlantic Ocean. Nevertheless, sporadic Pacific air masses arrivals, and strong cold waves coming from southern South America reach this altitude site. In spite of post-depositional effects, we were able to identify two strong ENSO (El Niño-Southern Oscillation) event signatures (1982-1983 and 1992) and the eruptive activity of the nearby Sabancaya volcano (1994).

Prospecting Glacial Ages and Paleoclimatic Reconstructions Northeastward of Nevado Coropuna (16° S, 73° W, 6377 m), Arid Tropical Andes

“…However, pollen within the Coropuna glaciers reveal different air masses fluxes. Herreros et al [59] drilled an ice core at 6080 m altitude, on the Coropuna northern slope, identifying pollen taxa that currently do not exist in that volcanic complex [60,61]: -Quercus and Podocarpus: from the Amazon basin, ~300 km northeastward. -Nothofagus: native of Patagonia, >3000 km toward the south.…”

“…The black triangles mark two summits, the highest toward northwest and the lower eastward. Mean annual precipitation isohyets map (mm/year) from PISCO.1.0 dataset [59]. The black triangles mark two summits, the highest toward northwest and the lower eastward.…”

“…This is how the ELA was estimated in the Santiago and Queñua Ranra valleys: ELA 2010 = 5984 m/BR = 1.0 (Table 2). In addition, the reconstruction of glaciers at their maximum extension, toward the northeast of Coropuna (Figure 7), enabled the paleoELA to be calculated (Tables 3 and 4 The paleoELA depression estimate, that is, its difference in altitude (m) with respect to the ELA 2010 , enabled the evaluation of the paleoclimate cooling with respect to the present, in the same phases (Table 5) Finally, the availability of paleoELA 2 and the cooling ∆T 2 , served to evaluate the paleoprecipitation at 6080 m, the ice core altitude [59], for two ATLR values (Table 6):…”

The potential effects of percolating snowmelt on palynological records from firn and glacier ice

“…Heusser, 1954;Fredskild and Wagner, 1974;Lichti-Federovich, 1974, 1975aMcAndrews, 1984;Bourgeois and others, 1985Bourgeois and others, , 2000Bourgeois and others, , 2001Short and Holdsworth, 1985;Bourgeois, 1986Bourgeois, , 1990Bourgeois, , 2000Koerner and others, 1988;Gajewski and others, 1995;Andreev and others, 1997), then the tropics (e.g. Liu, 2002, 2005a,b;Reese and others, 2003;others, 2005, 2007;Herreros and others, 2009) and finally to mid-latitude snow and ice (e.g. Nakazawa and others, 2004Nakazawa and others, , 2005Nakazawa and others, , 2011Nakazawa and others, , 2012Uetake andothers, 2006, Nakazawa andSuzuki, 2008).…”

“…Liu and others, 2005;Reese and others, 2013) and atmospheric circulation research (e.g. others, 1985, 2001;Short and Holdsworth, 1985;Liu, 2002, 2005a,b;Reese and others, 2003;Liu and others, 2007;Herreros and others, 2009). However, little attention has been given to understanding the modern pollen processes of deposition, entrainment and transport and other post-depositional processes on snowfields and how they affect pollen stratigraphy within snow and ice records.…”