Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 9 of 9

Full-Text Articles in Physical Sciences and Mathematics

Enhanced Recent Local Moisture Recycling On The Northwestern Tibetan Plateau Deduced From Ice Core Deuterium Excess Records, Wenling An, Shugui Hou, Qiong Zhang, Wangbin Zhang, Shuang-Ye Wu, Hao Xu, Hongxi Pang, Yetang Wang, Yaping Liu Dec 2017

Enhanced Recent Local Moisture Recycling On The Northwestern Tibetan Plateau Deduced From Ice Core Deuterium Excess Records, Wenling An, Shugui Hou, Qiong Zhang, Wangbin Zhang, Shuang-Ye Wu, Hao Xu, Hongxi Pang, Yetang Wang, Yaping Liu

Geology Faculty Publications

Local moisture recycling plays an essential role in maintaining an active hydrological cycle of the Tibetan Plateau (TP). Previous studies were largely limited to the seasonal time scale due to short and sparse observations, especially for the northwestern TP. In this study, we used a two‐component mixing model to estimate local moisture recycling over the past decades from the deuterium excess records of two ice cores (i.e., Chongce and Zangser Kangri) from the northwestern TP. The results show that on average almost half of the precipitation on the northwestern TP is provided by local moisture recycling. In addition, the local …


Snow Accumulation Variability Over The West Antarctic Ice Sheet Since 1900: A Comparison Of Ice Core Records With Era‐20c Reanalysis, Yetang Wang, Elizabeth R. Thomas, Shugui Hou, Baojuan Huai, Shuang-Ye Wu, Weijun Sun, Shanzhong Qi, Minghu Ding, Yulun Zhang Nov 2017

Snow Accumulation Variability Over The West Antarctic Ice Sheet Since 1900: A Comparison Of Ice Core Records With Era‐20c Reanalysis, Yetang Wang, Elizabeth R. Thomas, Shugui Hou, Baojuan Huai, Shuang-Ye Wu, Weijun Sun, Shanzhong Qi, Minghu Ding, Yulun Zhang

Geology Faculty Publications

This study uses a set of 37 firn core records over the West Antarctic Ice Sheet (WAIS) to test the performance of the twentieth century from the European Centre for Medium‐Range Weather Forecasts (ERA‐20C) reanalysis for snow accumulation and quantify temporal variability in snow accumulation since 1900. The firn cores are allocated to four geographical areas demarcated by drainage divides (i.e., Antarctic Peninsula (AP), western WAIS, central WAIS, and eastern WAIS) to calculate stacked records of regional snow accumulation. Our results show that the interannual variability in ERA‐20C precipitation minus evaporation (P − E) agrees well with the corresponding ice …


A High‐Resolution Atmospheric Dust Record For 1810–2004 A.D. Derived From An Ice Core In Eastern Tien Shan, Central Asia, Wangbin Zhang, Shugui Hou, Yaping Liu, Shuang-Ye Wu, Wenling An, Hongxi Pang, Chaomin Wang Jul 2017

A High‐Resolution Atmospheric Dust Record For 1810–2004 A.D. Derived From An Ice Core In Eastern Tien Shan, Central Asia, Wangbin Zhang, Shugui Hou, Yaping Liu, Shuang-Ye Wu, Wenling An, Hongxi Pang, Chaomin Wang

Geology Faculty Publications

Centennial‐scale, high‐resolution records of atmospheric dust conditions are rare in the arid and semiarid regions of central Asia, limiting our understanding of the regional climate and environmental changes and their potential driving forces. In this paper, we present an annually resolved atmospheric dust record covering the period of 1810–2004 A.D., reconstructed from an ice core retrieved at 4512 m above sea level from the Miaoergou Glacier in the eastern Tien Shan. The time series of dust flux for the past 195 years shows three periods of relatively low values (i.e., 1810–1829 A.D., 1863–1940 A.D., and 1979–2004 A.D.) and two periods …


Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Marie D. Jackson, Sean R. Mulcahy, Heng Chen, Yao Li, Qinfei Li, Piergiulio Cappelletti, Hans-Rudolf Wenk Jul 2017

Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Marie D. Jackson, Sean R. Mulcahy, Heng Chen, Yao Li, Qinfei Li, Piergiulio Cappelletti, Hans-Rudolf Wenk

Geology Faculty Publications

Pozzolanic reaction of volcanic ash with hydrated lime is thought to dominate the cementing fabric and durability of 2000-year-old Roman harbor concrete. Pliny the Elder, however, in first century CE emphasized rock-like cementitious processes involving volcanic ash (pulvis) “that as soon as it comes into contact with the waves of the sea and is submerged becomes a single stone mass (fierem unum lapidem), impregnable to the waves and every day stronger” (Naturalis Historia 35.166). Pozzolanic crystallization of Al-tobermorite, a rare, hydrothermal, calcium-silicate-hydrate mineral with cation exchange capabilities, has been previously recognized in relict lime clasts …


Explosive Processes During The 2015 Eruption Of Axial Seamount, As Recorded By Seafloor Hydrophones, Jacqueline Caplan-Auerbach, R. P. Dziak, J. Haxel, D. R. Bohnenstiehl, C. Garcia Apr 2017

Explosive Processes During The 2015 Eruption Of Axial Seamount, As Recorded By Seafloor Hydrophones, Jacqueline Caplan-Auerbach, R. P. Dziak, J. Haxel, D. R. Bohnenstiehl, C. Garcia

Geology Faculty Publications

Following the installation of the Ocean Observatories Initiative cabled array, the 2015 eruption of Axial Seamount, Juan de Fuca ridge, became the first submarine eruption to be captured in real time by seafloor seismic and acoustic instruments. This eruption also marked the first instance where the entire eruption cycle of a submarine volcano, from the previous eruption in 2011 to the end of the month-long 2015 event, was monitored continuously using autonomous ocean bottom hydrophones. Impulsive sounds associated with explosive lava-water interactions are identified within hydrophone records during both eruptions. Explosions within the caldera are acoustically distinguishable from those occurring …


Impact Of Icebergs On Net Primary Productivity In The Southern Ocean, Shuang-Ye Wu, Shugui Hou Mar 2017

Impact Of Icebergs On Net Primary Productivity In The Southern Ocean, Shuang-Ye Wu, Shugui Hou

Geology Faculty Publications

Productivity in the Southern Ocean (SO) is iron-limited, and supply of iron dissolved from aeolian dust is believed to be the main source from outside the marine environment. However, recent studies show that icebergs could provide a comparable amount of bioavailable iron to the SO as aeolian dust. In addition, small-scale areal studies suggest increased concentrations of chlorophyll, krill, and seabirds surrounding icebergs. Based on previous research, this study aims to examine whether iceberg occurrence has a significant impact on marine productivity at the scale of the SO, using remote sensing data of iceberg occurrences and ocean net primary productivity …


Delayed Warming Hiatus Over The Tibetan Plateau, Wenling An, Shugui Hou, Yongyun Hu, Shuang-Ye Wu Mar 2017

Delayed Warming Hiatus Over The Tibetan Plateau, Wenling An, Shugui Hou, Yongyun Hu, Shuang-Ye Wu

Geology Faculty Publications

A reduction in the warming rate for the global surface temperature since the late 1990s has attracted much attention and caused a great deal of controversy. During the same time period, however, most previous studies have reported enhanced warming over the Tibetan Plateau (TP). In this study we further examined the temperature trend of the TP and surrounding areas based on the homogenized temperature records for the period 1980–2014, we found that for the TP regions lower than 4000 m the warming rate has started to slow down since the late 1990s, a similar pattern consistent with the whole China …


Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Sean R. Mulcahy, Marie D. Jackson, Heng Chen, Yao Li, Piergiulio Cappelletti, Hans-Rudolf Wenk Jan 2017

Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Sean R. Mulcahy, Marie D. Jackson, Heng Chen, Yao Li, Piergiulio Cappelletti, Hans-Rudolf Wenk

Geology Faculty Publications

Pozzolanic reaction of volcanic ash with hydrated lime is thought to dominate the cementing fabric and durability of 2000-year-old Roman harbor concrete. Pliny the Elder, however, in first century CE emphasized rock-like cementitious processes involving volcanic ash (pulvis) “that as soon as it comes into contact with the waves of the sea and is submerged becomes a single stone mass (fierem unum lapidem), impregnable to the waves and every day stronger” (Naturalis Historia 35.166). Pozzolanic crystallization of Al-tobermorite, a rare, hydrothermal, calcium-silicate-hydrate mineral with cation exchange capabilities, has been previously recognized in relict lime clasts of the concrete. Synchrotron-based X-ray …


A Pulsed-Air Model Of Blue Whale B Call Vocalizations, R. P. Dziak, J. H. Haxel, T-K. Lau, S. Heimlich, Jacqueline Caplan-Auerbach, D. K. Mellinger, H. Matsumoto, B. Mate Jan 2017

A Pulsed-Air Model Of Blue Whale B Call Vocalizations, R. P. Dziak, J. H. Haxel, T-K. Lau, S. Heimlich, Jacqueline Caplan-Auerbach, D. K. Mellinger, H. Matsumoto, B. Mate

Geology Faculty Publications

Blue whale sound production has been thought to occur by Helmholtz resonance via air flowing from the lungs into the upper respiratory spaces. This implies that the frequency of blue whale vocalizations might be directly proportional to the size of their sound-producing organs. Here we present a sound production mechanism where the fundamental and overtone frequencies of blue whale B calls can be well modeled using a series of short-duration (<1 >s) wavelets. We propose that the likely source of these wavelets are pneumatic pulses caused by opening and closing of respiratory valves during air recirculation between the lungs and …