Towards orbital dating of the EPICA Dome C ice core using deltaO2/N2

first_imgBased on a composite of several measurement series performed on ice samples stored at −25 °C or −50 °C, we present and discuss the first δO2/N2 record of trapped air from the EPICA Dome C (EDC) ice core covering the period between 300 and 800 ka (thousands of years before present). The samples stored at −25 °C show clear gas loss affecting the precision and mean level of the δO2/N2 record. Two different gas loss corrections are proposed to account for this effect, without altering the spectral properties of the original datasets. Although processes at play remain to be fully understood, previous studies have proposed a link between surface insolation, ice grain properties at close-off, and δO2/N2 in air bubbles, from which orbitally tuned chronologies of the Vostok and Dome Fuji ice core records have been derived over the last four climatic cycles. Here, we show that limitations caused by data quality and resolution, data filtering, and uncertainties in the orbital tuning target limit the precision of this tuning method for EDC. Moreover, our extended record includes two periods of low eccentricity. During these intervals (around 400 ka and 750 ka), the matching between δO2/N2 and the different insolation curves is ambiguous because some local insolation maxima cannot be identified in the δO2/N2 record (and vice versa). Recognizing these limitations, we restrict the use of our δO2/N2 record to show that the EDC3 age scale is generally correct within its published uncertainty (6 kyr) over the 300–800 ka period.last_img read more

No extra pay for Elkhart County Emergency Management workers

first_img Google+ No extra pay for Elkhart County Emergency Management workers Facebook Pinterest Facebook By Carl Stutsman – July 14, 2020 0 300 Google+ Twitter IndianaLocalNews WhatsApp Twitter Pinterest (“The Fall of Madoff” by frankieleon, CC BY 2.0) The Elkhart County Council has voted against giving extra pay to several county workers for the additional hours they’ve put in during the COVID-19 pandemic.Emergency Management Director Jennifer Tobey proposed the additional pay to commissioners, noting that as a department head neither she nor many of her colleagues could ever have imagined the amount of work they’ve put in. Tobey said that she has regularly worked 16-18 hour days since mid march.The requested money would have come out of CARES act money given to the county from the federal government. Speaking against the additional pay, The Elkhart Truth reports Councilman Tom Stump suggested that the extra work is part of their job as they were hired to handle emergencies.The proposal fell with a 5-2 vote. WhatsApp Previous articleFour Winds New Buffalo opens its sports bookNext articleMan arrested for using stolen ID to take money from bank Carl Stutsmanlast_img read more