128 research outputs found
High-resolution mineral dust and sea ice proxy records from the Talos Dome ice core
No full textIn this study we report on new non-sea salt calcium (nssCa2+, mineral dust proxy) and sea salt sodium (ssNa+, sea ice proxy) records along the East Antarctic Talos Dome deep ice core in centennial resolution reaching back 150 thousand years (ka) before present. During glacial conditions nssCa2+ fluxes in Talos Dome are strongly related to temperature as has been observed before in other deep Antarctic ice core records, and has been associated with synchronous changes in the main source region (southern South America) during climate variations in the last glacial. However, during warmer climate conditions Talos Dome mineral dust input is clearly elevated compared to other records mainly due to the contribution of additional local dust sources in the Ross Sea area. Based on a simple transport model, we compare nssCa2+ fluxes of different East Antarctic ice cores. From this multi-site comparison we conclude that changes in transport efficiency or atmospheric lifetime of dust particles do have a minor effect compared to source strength changes on the large-scale concentration changes observed in Antarctic ice cores during climate variations of the past 150 ka. Our transport model applied on ice core data is further validated by climate model data.
The availability of multiple East Antarctic nssCa2+ records also allows for a revision of a former estimate on the atmospheric CO2 sensitivity to reduced dust induced iron fertilisation in the Southern Ocean during the transition from the Last Glacial Maximum to the Holocene (T1). While a former estimate based on the EPICA Dome C (EDC) record only suggested 20 ppm, we find that reduced dust induced iron fertilisation in the Southern Ocean may be responsible for up to 40 ppm of the total atmospheric CO2 increase during T1. During the last interglacial, ssNa+ levels of EDC and EPICA Dronning Maud Land (EDML) are only half of the Holocene levels, in line with higher temperatures during that period, indicating much reduced sea ice extent in the Atlantic as well as the Indian Ocean sector of the Southern Ocean. In contrast, Holocene ssNa+ flux in Talos Dome is about the same as during the last interglacial, indicating that there was similar ice cover present in the Ross Sea area during MIS 5.5 as during the Holocene
A Generalized Procedure for Constructing Fractional Replicates
No full text39 pages, 1 article*A Generalized Procedure for Constructing Fractional Replicates* (Paik, U. B.; Federer, W. T.) 39 page
On the Construction of Fractional Replicates with Special Reference to Saturated Designs
No full text33 pages, 1 article*On the Construction of Fractional Replicates with Special Reference to Saturated Designs* (Paik, U. B.; Federer, W. T.) 33 page
On a Randomized Procedure for Saturated Fractional Replicates in a 2 [n] -Factorial
No full text11 pages, 1 article*On a Randomized Procedure for Saturated Fractional Replicates in a 2 [n] -Factorial* (Paik, U. B.; Federer, W. T.) 11 page
On Construction of Fractional Replicates and on Aliasing Schemes
No full text47 pages, 1 article*On Construction of Fractional Replicates and on Aliasing Schemes* (Paik, U. B.; Federer, W. T.) 47 page
Analysis of Binary Number Association Scheme Partially Balanced Designs
No full text46 pages, 1 article*Analysis of Binary Number Association Scheme Partially Balanced Designs* (Paik, U. B.; Federer, W. T.) 46 page
On PA Type Incomplete Block Designs and PAB Type Rectangular Designs
No full text30 pages, 1 article*On PA Type Incomplete Block Designs and PAB Type Rectangular Designs* (Paik, U. B.; Federer, W. T.) 30 page
Analysis of Non-Orthogonal n-Way Classifications and Fractional Replication
No full text44 pages, 1 article*Analysis of Non-Orthogonal n-Way Classifications and Fractional Replication* (Paik, U. B.; Federer, W. T.) 44 page
Partially Balanced Designs and Properties A and B
No full textThis issue was undated. The date given is an estimate.22 pages, 1 article*Partially Balanced Designs and Properties A and B* (Paik, U. B.; Federer, W. T.) 22 page
A Generalized Method of Analysis of Factorial Experiment with Unequal Number of Observations
No full textThis issue was undated. The date given is an estimate.37 pages, 1 article*A Generalized Method of Analysis of Factorial Experiment with Unequal Number of Observations* (Paik, U. B.; Federer, W. T.) 37 page
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