Climate influences on water and sediment properties of Genovesa Crater Lake, Galápagos

Jessica L. Conroy, Diane M. Thompson, Aaron Collins, Jonathan Overpeck, Mark B. Bush, Julia Cole

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Genovesa Crater Lake is a remote, hypersaline lake in the northern Galápagos archipelago that contains a finely laminated sediment record. This sediment record has the potential to provide a high-resolution history of past climate variability in the eastern tropical Pacific. Here we present modern climate, lake, and sediment observations from 2009 to 2012 to explore how local climate variability influences Genovesa Crater Lake and its sediments. Surface lake temperature is strongly linked to air temperature and is highly seasonal. Temperature stratification is strongest during the warm season, whereas temperature becomes more uniform through the water column in the cool season. Deeper and earlier mixing occurred during the 2010 La Niña, which subsequently delayed 2011 cool season mixing and maximum warm season surface temperatures in 2011 and 2012. Lake salinity changes are influenced by precipitation, evaporation and persistent seawater influx. The largest declines in subsurface salinity follow months after the rainy season, when temperatures cool and fresher surface water from the previous warm/wet season mixes into the subsurface. Between 2009 and 2012, more calcium carbonate precipitated during a period of higher salinity. The period of highest calcium carbonate abundance measured in sediment records that span the late nineteenth to twentieth century coincides with the failure of two consecutive rainy seasons in 1988 and 1989 as well as the coldest monthly sea surface temperature measured at Puerto Ayora in 1989. More calcium carbonate-rich laminae from AD 1550 ± 70 to 1675 ± 90 may indicate a greater frequency of prolonged droughts or cooler temperatures, although enhanced productivity may also modulate carbonate precipitation. More Ca-rich laminae in Genovesa coincide with dry conditions inferred from other Galápagos sediment proxies, as well as prolonged dry and cool conditions inferred from reconstructions of the Southern Oscillation Index and NINO3 sea surface temperatures.

Original languageEnglish (US)
Pages (from-to)331-347
Number of pages17
JournalJournal of Paleolimnology
Volume52
Issue number4
DOIs
StatePublished - 2014

Fingerprint

crater lake
sediment property
climate
lakes
sediments
warm season
calcium carbonate
sediment
surface temperature
wet season
water
lake
salinity
temperature
sea surface temperature
Southern Oscillation
coolers
temperature profiles
twentieth century
carbonates

Keywords

  • ENSO
  • Galápagos
  • Hypersaline lake
  • Tropical Pacific

ASJC Scopus subject areas

  • Aquatic Science
  • Earth-Surface Processes

Cite this

Climate influences on water and sediment properties of Genovesa Crater Lake, Galápagos. / Conroy, Jessica L.; Thompson, Diane M.; Collins, Aaron; Overpeck, Jonathan; Bush, Mark B.; Cole, Julia.

In: Journal of Paleolimnology, Vol. 52, No. 4, 2014, p. 331-347.

Research output: Contribution to journalArticle

Conroy, Jessica L. ; Thompson, Diane M. ; Collins, Aaron ; Overpeck, Jonathan ; Bush, Mark B. ; Cole, Julia. / Climate influences on water and sediment properties of Genovesa Crater Lake, Galápagos. In: Journal of Paleolimnology. 2014 ; Vol. 52, No. 4. pp. 331-347.
@article{24cf9ce477544834a4a2ec6b97bdf663,
title = "Climate influences on water and sediment properties of Genovesa Crater Lake, Gal{\'a}pagos",
abstract = "Genovesa Crater Lake is a remote, hypersaline lake in the northern Gal{\'a}pagos archipelago that contains a finely laminated sediment record. This sediment record has the potential to provide a high-resolution history of past climate variability in the eastern tropical Pacific. Here we present modern climate, lake, and sediment observations from 2009 to 2012 to explore how local climate variability influences Genovesa Crater Lake and its sediments. Surface lake temperature is strongly linked to air temperature and is highly seasonal. Temperature stratification is strongest during the warm season, whereas temperature becomes more uniform through the water column in the cool season. Deeper and earlier mixing occurred during the 2010 La Ni{\~n}a, which subsequently delayed 2011 cool season mixing and maximum warm season surface temperatures in 2011 and 2012. Lake salinity changes are influenced by precipitation, evaporation and persistent seawater influx. The largest declines in subsurface salinity follow months after the rainy season, when temperatures cool and fresher surface water from the previous warm/wet season mixes into the subsurface. Between 2009 and 2012, more calcium carbonate precipitated during a period of higher salinity. The period of highest calcium carbonate abundance measured in sediment records that span the late nineteenth to twentieth century coincides with the failure of two consecutive rainy seasons in 1988 and 1989 as well as the coldest monthly sea surface temperature measured at Puerto Ayora in 1989. More calcium carbonate-rich laminae from AD 1550 ± 70 to 1675 ± 90 may indicate a greater frequency of prolonged droughts or cooler temperatures, although enhanced productivity may also modulate carbonate precipitation. More Ca-rich laminae in Genovesa coincide with dry conditions inferred from other Gal{\'a}pagos sediment proxies, as well as prolonged dry and cool conditions inferred from reconstructions of the Southern Oscillation Index and NINO3 sea surface temperatures.",
keywords = "ENSO, Gal{\'a}pagos, Hypersaline lake, Tropical Pacific",
author = "Conroy, {Jessica L.} and Thompson, {Diane M.} and Aaron Collins and Jonathan Overpeck and Bush, {Mark B.} and Julia Cole",
year = "2014",
doi = "10.1007/s10933-014-9797-z",
language = "English (US)",
volume = "52",
pages = "331--347",
journal = "Journal of Paleolimnology",
issn = "0921-2728",
publisher = "Springer Netherlands",
number = "4",

}

TY - JOUR

T1 - Climate influences on water and sediment properties of Genovesa Crater Lake, Galápagos

AU - Conroy, Jessica L.

AU - Thompson, Diane M.

AU - Collins, Aaron

AU - Overpeck, Jonathan

AU - Bush, Mark B.

AU - Cole, Julia

PY - 2014

Y1 - 2014

N2 - Genovesa Crater Lake is a remote, hypersaline lake in the northern Galápagos archipelago that contains a finely laminated sediment record. This sediment record has the potential to provide a high-resolution history of past climate variability in the eastern tropical Pacific. Here we present modern climate, lake, and sediment observations from 2009 to 2012 to explore how local climate variability influences Genovesa Crater Lake and its sediments. Surface lake temperature is strongly linked to air temperature and is highly seasonal. Temperature stratification is strongest during the warm season, whereas temperature becomes more uniform through the water column in the cool season. Deeper and earlier mixing occurred during the 2010 La Niña, which subsequently delayed 2011 cool season mixing and maximum warm season surface temperatures in 2011 and 2012. Lake salinity changes are influenced by precipitation, evaporation and persistent seawater influx. The largest declines in subsurface salinity follow months after the rainy season, when temperatures cool and fresher surface water from the previous warm/wet season mixes into the subsurface. Between 2009 and 2012, more calcium carbonate precipitated during a period of higher salinity. The period of highest calcium carbonate abundance measured in sediment records that span the late nineteenth to twentieth century coincides with the failure of two consecutive rainy seasons in 1988 and 1989 as well as the coldest monthly sea surface temperature measured at Puerto Ayora in 1989. More calcium carbonate-rich laminae from AD 1550 ± 70 to 1675 ± 90 may indicate a greater frequency of prolonged droughts or cooler temperatures, although enhanced productivity may also modulate carbonate precipitation. More Ca-rich laminae in Genovesa coincide with dry conditions inferred from other Galápagos sediment proxies, as well as prolonged dry and cool conditions inferred from reconstructions of the Southern Oscillation Index and NINO3 sea surface temperatures.

AB - Genovesa Crater Lake is a remote, hypersaline lake in the northern Galápagos archipelago that contains a finely laminated sediment record. This sediment record has the potential to provide a high-resolution history of past climate variability in the eastern tropical Pacific. Here we present modern climate, lake, and sediment observations from 2009 to 2012 to explore how local climate variability influences Genovesa Crater Lake and its sediments. Surface lake temperature is strongly linked to air temperature and is highly seasonal. Temperature stratification is strongest during the warm season, whereas temperature becomes more uniform through the water column in the cool season. Deeper and earlier mixing occurred during the 2010 La Niña, which subsequently delayed 2011 cool season mixing and maximum warm season surface temperatures in 2011 and 2012. Lake salinity changes are influenced by precipitation, evaporation and persistent seawater influx. The largest declines in subsurface salinity follow months after the rainy season, when temperatures cool and fresher surface water from the previous warm/wet season mixes into the subsurface. Between 2009 and 2012, more calcium carbonate precipitated during a period of higher salinity. The period of highest calcium carbonate abundance measured in sediment records that span the late nineteenth to twentieth century coincides with the failure of two consecutive rainy seasons in 1988 and 1989 as well as the coldest monthly sea surface temperature measured at Puerto Ayora in 1989. More calcium carbonate-rich laminae from AD 1550 ± 70 to 1675 ± 90 may indicate a greater frequency of prolonged droughts or cooler temperatures, although enhanced productivity may also modulate carbonate precipitation. More Ca-rich laminae in Genovesa coincide with dry conditions inferred from other Galápagos sediment proxies, as well as prolonged dry and cool conditions inferred from reconstructions of the Southern Oscillation Index and NINO3 sea surface temperatures.

KW - ENSO

KW - Galápagos

KW - Hypersaline lake

KW - Tropical Pacific

UR - http://www.scopus.com/inward/record.url?scp=84922004290&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84922004290&partnerID=8YFLogxK

U2 - 10.1007/s10933-014-9797-z

DO - 10.1007/s10933-014-9797-z

M3 - Article

AN - SCOPUS:84922004290

VL - 52

SP - 331

EP - 347

JO - Journal of Paleolimnology

JF - Journal of Paleolimnology

SN - 0921-2728

IS - 4

ER -