Holocene hydrologic variation at Lake Titicaca, Bolivia/Peru, and its relationship to North Atlantic climate variation

Abstract

Follow this and additional works at: http://digitalcommons.unl.edu/geosciencefacpub Part of the Earth Sciences CommonsThis Article is brought to you for free and open access by the Earth and Atmospheric Sciences, Department of at DigitalCommons@University of Nebraska -Lincoln. It has been accepted for inclusion in Papers in the Earth and Atmospheric Sciences by an authorized administrator of DigitalCommons@University of Nebraska -Lincoln.Baker, P. A.; Fritz, Sherilyn C.; Garland, J.; and Ekdahl, E., "Holocene hydrologic variation at Lake Titicaca, Bolivia/Peru, and its relationship to North Atlantic climate variation" (2005). Papers in the Earth and Atmospheric Sciences. 37. http://digitalcommons.unl.edu/geosciencefacpub/37 IntroductionRecent studies from many sites in the Northern Hemisphere show centennial-to millennial-scale climate variation that has been correlated directly with changes in atmospheric radiocarbon production or with changes in North Atlantic oceanic circulation that also may be linked to atmospheric radiocarbon production and presumed solar variability (e.g. Bond et al., 1997Bond et al., , 2001Hodell et al., 2001;Neff et al., 2001;Fleitmann et al., 2003;Hu et al., 2003;Rohling and Pälike, 2005;Wang et al., 2005). However, despite a growing body of palaeoclimatic data from the Southern Hemisphere tropics of South America, patterns of hydrologic variation at these timescales are not as well known, because of the lack of records at suitably high resolution that span the entire Holocene. Thus, it is unclear how centennial-to-millennial variability in the climate system is manifest in the region, and how (or whether) these changes are correlated with climatic events in the Northern Hemisphere. In this paper we will address two questions: is there evidence in the Holocene record of Lake Titicaca for climatic changes that correlate with "Bond events" (Bond et al., 1997) of the North Atlantic and, if so, what is the phasing of these Altiplano events with respect to records from the North Atlantic and the Indian/Asian monsoon regions?Site description Lake Titicaca (16° S, 69° W) lies at 3810 m on the Altiplano of Boliva and Peru (Fig. 1), a high-elevation internally drained plateau. The lake consists of a large (7131 km 2 ) deep (maximum depth 284 m; mean depth 125 m) main basin and a smaller (1428 km 2 ) shallow basin (maximum depth 42 m; mean depth 9 m), connected at the Straits of Tiquina (25 m depth). Hydrologic inputs to the contemporary lake are balanced between direct rainfall (47%) and inflow from six major rivers (53%). Modern water export is primarily via evaporation (91%), with <9% loss via the sole surface outlet, the Rio Desaguadero at 3804 m elevation (Roche et al., 1992 AbstractA growing number of sites in the Northern Hemisphere show centennial-to millennial-scale climate variation that has been correlated with change in solar variability or with change in North Atlantic circulation. However, it is unclear how (or whether) these oscillations in the climate system are manifest in the ...

The Nature and Origin of Decadal to Millennial Scale Climate Variability in the Southern Tropics of South America: The Holocene Record of Lago Umayo, Peru

“…On sub-orbital time-scales, several studies have shown that throughout the southern South American tropics, precipitation amount is elevated during North Atlantic cold events (Baker et al 2005). Again the speleothem records illustrate this best for the late Pleistocene.…”

Paleolimnological evidence of the effects on lakes of energy and mass transfer from climate and humans

“…For example, analysis of more than 80 yr of meteorological and historical records from Lake Titicaca in the tropical Andes demonstrates that lake level has varied ,7 m during the 20th century, with lake levels decreasing during El Niñ o events, rising with La Niñ a episodes, and varying on decadal time scales because of long-term changes in sea-surface temperature (SST) and resultant atmospheric linkages in the tropical North Atlantic Ocean (Baker et al 2001b). Importantly, sedimentary analyses demonstrate that past lake levels have been much more variable than at present, with historical changes of about 20 m occurring at centennial and millennial scales because of the effects of abrupt cooling of the high-latitude North Atlantic Ocean and its effects on SST gradients in tropics (Baker et al 2005). Even larger lake-level declines have resulted from variations in the South American summer monsoon driven by changes in orbital precession on 20,000-yr cycles (75 m) (Baker et al 2001a,b), and orbital eccentricities at scales of 100,000 yr (200 m) (Fritz et al 2007).…”

Quantifying and specifying the solar influence on terrestrial surface temperature

“…Holzhauser et al (2005) compared glacier and lake level fluctuations in westcentral Europe over the last 3500 years and demonstrated synchronicity between glacier advances, periods of higher lake levels and maxima of atmospheric radiocarbon. There are numerous other examples of sediment and lake level data that point to a solar link (Baker et al, 2005;Morrill et al, 2006;Patterson et al, 2004;Stager et al, 2005;Verschuren et al, 2000;Wu et al, 2006;Haltia-Hovi et al, 2007).…”