Wax Lips Lake, NW Greenland Holocene and Last Interglacial Chironomid Inferred Temperature McFarlin, J.M.; Axford, Y.; Osburn, M.R.; Kelly, M.A.; Osterberg, E.; Farnsworth, L.B. McFarlin, J.M. Axford, Y. Osburn, M.R. Kelly, M.A. Osterberg, E. Farnsworth, L.B. earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Tribe Pentaneurini) earth science/paleoclimate/climate reconstructions|insect|paleolimnology (depth,null,null,centimeter,null,climate reconstructions|insect|paleolimnology,null,null,N,depth measured from top of core) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Chironomus) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Psectrocladius) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Stictochironomus) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Cricotopus/Orthocladius) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Paracladius) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Psuedodiamesa) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Corynoneura/Thienemanniella) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Hydrobaenus/Oliveridia) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Zalutschia) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,subtribe Tanytarsini) earth science/paleoclimate/insect|paleolimnology (total head capsules,null,null,count,null,insect|paleolimnology,null,null,N,raw count of whole midge head capsules that were no ID + unknown) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Procladius-type) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Sergentia) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Heterotrissicladius) earth science/paleoclimate/insect|paleolimnology (total head capsules,null,null,count per gram,null,insect|paleolimnology,null,null,N,total whole head capsules per gram wet sediment) earth science/paleoclimate/climate reconstructions|insect|paleolimnology (air temperature,midge assemblage,null,degree Celsius,Jul,climate reconstructions|insect|paleolimnology,null,null,N,weighted-average model with tolerance down-weighting and inverse-deshrinking and bootstrapping using Francis et al (2006) training set) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Eukiefferiella/Tvetenia) earth science/paleoclimate/insect|paleolimnology (identified midge,null,null,percent,null,insect|paleolimnology,null,null,N,Chaoborus) earth science/paleoclimate/insecta (Wax Lips Lake>LATITUDE 76.852>LONGITUDE -66.959) Projections of future rates of mass loss from the Greenland Ice Sheet are highly uncertain because its sensitivity to warming is unclear. Geologic reconstructions of Quaternary interglacials can illustrate how the ice sheet responded during past warm periods, providing insights into ice sheet behavior and important tests for data-model comparisons. However, paleoclimate records from Greenland are limited: Early Holocene peak warmth has been quantified at only a few sites, and terrestrial sedimentary records of prior interglacials are exceptionally rare due to glacial erosion during the last glacial period. Here, we discuss findings from a lacustrine archive that records both the Holocene and the Last Interglacial (LIG) from Greenland, allowing for direct comparison between two interglacials. Sedimentary chironomid assemblages indicate peak July temperatures 4.0 to 7.0 C warmer than modern during the Early Holocene maximum in summer insolation. Chaoborus and chironomids in LIG sediments indicate July temperatures at least 5.5 to 8.5 C warmer than modern. These estimates indicate pronounced warming in northwest Greenland during both interglacials. This helps explain dramatic ice sheet thinning at Camp Century in northwest Greenland during the Early Holocene and, for the LIG, aligns with controversial estimates of Eemian warming from ice core data retrieved in northern Greenland. Converging geologic evidence for strong LIG warming is challenging to reconcile with inferred Greenland Ice Sheet extent during the LIG, and the two appear incompatible in many models of ice sheet evolution. An increase in LIG snowfall could help resolve this problem, pointing to the need for hydroclimate reconstructions from the region. STUDY NOTES: Chironomid and Chaoborus assemblage data and midge-inferred temperature reconstructions for core 14WLL2A Wax Lips Lake in northwest Greenland through the Holocene and Last Interglacial NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : McFarlin, J.M. Investigator : Axford, Y. Investigator : Osburn, M.R. Investigator : Kelly, M.A. Investigator : Osterberg, E. Investigator : Farnsworth, L.B. 2018-06-04 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/23990 https://www1.ncdc.noaa.gov/pub/data/paleo/insecta/chironomidae/northamerica/greenland/waxlips2018cit.txt https://www1.ncdc.noaa.gov/pub/data/paleo/insecta/chironomidae/northamerica/greenland/waxlips2018cit.txt English https://www.ncdc.noaa.gov/paleo/study/23990 https://www1.ncdc.noaa.gov/pub/data/paleo/insecta/chironomidae/northamerica/greenland/waxlips2018cit.txt Jamie M. McFarlin, Yarrow Axford, Magdalena R. Osburn, Meredith A. Kelly, Erich C. Osterberg, Lauren B. Farnsworth2018Pronounced summer warming in northwest Greenland during the Holocene and Last InterglacialProceedings of the National Academy of Sciences10.1073/pnas.1720420115http://www.pnas.org/content/early/2018/05/30/1720420115 START YEAR: 120000 cal yr BP * END YEAR: 700 cal yr BP -66.959 76.852 -66.959 76.852