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Full-Text Articles in Physical Sciences and Mathematics
Impulsive Volcanic Plumes Generate Volcanic Lightning And Vent Discharges: A Statistical Analysis Of Sakurajima Volcano In 2015, Cassandra M. Smith, Damien Gaudin, Alexa R. Van Eaton, Sonja A. Behnke, Steven Reader, Ronald J. Thomas, Harald Edens, Stephen R. Mcnutt, Corrado Cimarelli
Impulsive Volcanic Plumes Generate Volcanic Lightning And Vent Discharges: A Statistical Analysis Of Sakurajima Volcano In 2015, Cassandra M. Smith, Damien Gaudin, Alexa R. Van Eaton, Sonja A. Behnke, Steven Reader, Ronald J. Thomas, Harald Edens, Stephen R. Mcnutt, Corrado Cimarelli
School of Geosciences Faculty and Staff Publications
The origin of electrical activity accompanying volcanic ash plumes is an area of heightened interest in volcanology. However, it is unclear how intense an eruption needs to be to produce lightning flashes as opposed to “vent discharges,” which represent the smallest scale of electrical activity. This study targets 97 carefully monitored plumesJapan, from June 1 to 7, 2015. We use multiparametric measurements from sensors including a nine-station lightning mapping array and an infrared camera to characterize plume ascent. Findings demonstrate that the impulsive, high velocity plumes (>55 m/s) were most likely to create vent discharges, whereas lightning flashes occurred …
Evaluating The Influences Of Harvesting Activity And Eutrophication On Loss Of Aquatic Vegetations In Taihu Lake, China, Juhua Luo, Ruiliang Pu, Hongtao Duan, Ronghua Ma, Zhigang Mao, Yuan Zeng, Linsheng Huang, Qitao Xiao
Evaluating The Influences Of Harvesting Activity And Eutrophication On Loss Of Aquatic Vegetations In Taihu Lake, China, Juhua Luo, Ruiliang Pu, Hongtao Duan, Ronghua Ma, Zhigang Mao, Yuan Zeng, Linsheng Huang, Qitao Xiao
School of Geosciences Faculty and Staff Publications
A rapid degradation of aquatic vegetations in Taihu Lake has roused a wide attention in recent years. Giving large-scale harvesting activity on aquatic vegetation since 2012, whether water eutrophication or the human harvest activity induced the degradation remains controversial and unclear. In this study, based on Landsat and HJ-CCD data acquired from 1984 to 2016 and a 12-year field observation (2005–2016) of water quality, a method was proposed to quantitatively assess impacts of harvesting activity and water quality change on degradations of both floating-leaved aquatic vegetation (FAV) and submerged aquatic vegetation (SAV) in Taihu Lake. First, areas of FAV and …
Mapping Long-Term Spatiotemporal Dynamics Of Pen Aquaculture In A Shallow Lake: Less Aquaculture Coming Along Better Water Quality, Juhua Luo, Ruiliang Pu, Ronghua Ma, Xiaolong Wang, Xijun Lai, Zhigang Mao, Li Zhang, Zhaoliang Peng, Zhe Sun
Mapping Long-Term Spatiotemporal Dynamics Of Pen Aquaculture In A Shallow Lake: Less Aquaculture Coming Along Better Water Quality, Juhua Luo, Ruiliang Pu, Ronghua Ma, Xiaolong Wang, Xijun Lai, Zhigang Mao, Li Zhang, Zhaoliang Peng, Zhe Sun
School of Geosciences Faculty and Staff Publications
Pen aquaculture is the main form of aquaculture in some shallow lakes in eastern China. It is valuable to map the spatiotemporal changes of pen aquaculture in eutrophic lakes to assess its effect on water quality, thereby helping the relevant decision-making agencies to manage the water quality (WQ) of lakes. In this study, an automatic approach for extracting the pen aquaculture area was developed based on Landsat data. The approach integrates five algorithms, including grey transformation, discrete wavelet transform, fast Fourier transform, singular value decomposition and k-nearest neighbor classification. It was successfully applied in the automatic mapping of the pen …
Fire And Flood Expand The Floodplain Shifting Habitat Mosaic Concept, W. J. Kleindl, Mark C. Rains, L. A. Marshall, F. R. Hauer
Fire And Flood Expand The Floodplain Shifting Habitat Mosaic Concept, W. J. Kleindl, Mark C. Rains, L. A. Marshall, F. R. Hauer
School of Geosciences Faculty and Staff Publications
The floodplain shifting habitat mosaic concept suggests that habitat patch dynamics are influenced by hydrologic disturbances driven by flood pulses of sufficient power to initiate incipient motion of the substratum and maintain cut-and-fill alluviation of the channel and banks. However, floodplain habitat mosaics are subject to other important landscape-scale disturbance regimes. In the Rocky Mountains of the USA and Canada, fire also affects floodplain habitat patch composition. The floodplain exists at the intersection of disturbance regimes that shape the riverscape and those that shape the landscape. We extended the shifting habitat mosaic concept by examining the effects of multiple disturbance …
Multi-Year Observations Of Breiðamerkurjökull, A Marine-Terminating Glacier In Southeastern Iceland, Using Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, Ian M. Howat, Noel Gourmelen, Chad Lembke, Charles L. Werner, Santiago De La Peña, Björn Oddsson
Multi-Year Observations Of Breiðamerkurjökull, A Marine-Terminating Glacier In Southeastern Iceland, Using Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, Ian M. Howat, Noel Gourmelen, Chad Lembke, Charles L. Werner, Santiago De La Peña, Björn Oddsson
School of Geosciences Faculty and Staff Publications
Terrestrial radar interferometry (TRI) is a new technique for studying ice motion and volume change of glaciers. TRI is especially useful for temporally and spatially dense measurements of highly dynamic glacial termini. We conducted a TRI survey of Breiðamerkurjökull, a marine-terminating glacier in Iceland, imaging its terminus near the end of the melt season in 2011, 2012 and 2013. The ice velocities were as high as 5 m d−1, with the fastest velocities near the calving front. Retreat of the glacier over the 3 year observation period was accompanied by strong embayment formation. Iceberg tracking with the radar shows high …
Evidence Of Atmospheric Gravity Waves During The 2008 Eruption Of Okmok Volcano From Seismic And Remote Sensing Observations, S. De Angelis, Stephen R. Mcnutt, P. W. Webley
Evidence Of Atmospheric Gravity Waves During The 2008 Eruption Of Okmok Volcano From Seismic And Remote Sensing Observations, S. De Angelis, Stephen R. Mcnutt, P. W. Webley
School of Geosciences Faculty and Staff Publications
Okmok volcano erupted on July 12, 2008, following an 11-year hiatus. Detailed inspection of the syn-eruptive seismograms revealed the presence of an ultra long-period mode at a frequency of 1.7 mHz, which is not a characteristic of the background seismic noise at Okmok. Data collected by the National Oceanic and Atmospheric Administration Geostationary Operational Environmental Satellite (GOES) and National Aeronautical and Space Administration Moderate Resolution Imaging Spectroradiometer (MODIS) sensors displayed the propagation of a vigorous ash-and-steam plume up to about 17 km above sea level. We suggest that the observed ultra long-period signals represent the response of the seismometer to …