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Articles 1 - 8 of 8
Full-Text Articles in Physical Sciences and Mathematics
Topography And Tropical Cyclone Structure Influence On Eyewall Evolution In Typhoon Sinlaku (2008), Cheng-Hsiang Chih, Kun-Hsuan Chou, Sen Chiao
Topography And Tropical Cyclone Structure Influence On Eyewall Evolution In Typhoon Sinlaku (2008), Cheng-Hsiang Chih, Kun-Hsuan Chou, Sen Chiao
Faculty Publications, Meteorology and Climate Science
Typhoon Sinlaku (2008) was a tropical system that affected many countries in East Asia. Besides the loss of life and economic damage, many scientific questions are associated with this system that need to be addressed. A series of numerical simulations were conducted in this study using V3.2 of the advanced research version of the Weather Research and Forecasting (WRF-ARW) model to examine the impacts of different terrain conditions and vortex structures on the eyewall evolution when Sinlaku was crossing Taiwan. The sensitivity experiments using different vortex structures show that a storm of the same intensity with a larger eyewall radius …
Comparisons Of Cirrus Cloud Properties Between Polluted And Pristine Air Based On In-Situ Observations From The Nasa Attrex, Nsf Hippo And Eu Inca Campaigns, Minghui Diao, Jorgen Jensen
Comparisons Of Cirrus Cloud Properties Between Polluted And Pristine Air Based On In-Situ Observations From The Nasa Attrex, Nsf Hippo And Eu Inca Campaigns, Minghui Diao, Jorgen Jensen
Faculty Publications, Meteorology and Climate Science
Cirrus clouds, covering about 30% of the Earth’s surface area, play an important role in the climate and weather systems. Cirrus cloud radiative forcing (cooling or warming) is influenced by their microphysical (e.g., ice crystal number concentration and size distribution) and macroscopic (e.g., spatial extent) properties. Currently it is still unclear how the formation of cirrus clouds and their microphysical properties are influenced by anthropogenic emissions. In this work, we use in-situ observations from three flight campaigns to compare the cirrus cloud properties between polluted and pristine regions. Our dataset includes: (1) the NASA Airborne Tropical Tropopause Experiment (ATTREX) campaign …
Distributions Of Ice Supersaturation And Ice Crystals From Airborne Observations In Relation To Upper Tropospheric Dynamical Boundaries, Minghui Diao, Jorgen Jensen, Laura Pan, Cameron Homeyer, Shawn Honomichl, James Bresch, Aaron Bansemer
Distributions Of Ice Supersaturation And Ice Crystals From Airborne Observations In Relation To Upper Tropospheric Dynamical Boundaries, Minghui Diao, Jorgen Jensen, Laura Pan, Cameron Homeyer, Shawn Honomichl, James Bresch, Aaron Bansemer
Faculty Publications, Meteorology and Climate Science
Ice supersaturation (ISS) is the prerequisite condition for cirrus cloud formation. To examine multiscale dynamics' influences on ISS formation, we analyze in situ aircraft observations (~200 m scale) over North America in coordinates relative to dynamical boundaries in the upper troposphere and lower stratosphere. Two case studies demonstrate that ISS formation is likely influenced by mesoscale uplifting, small-scale waves, and turbulence. A collective analysis of 15 flights in April–June 2008 shows that the top layers of ISS and ice crystal distributions are strongly associated with thermal tropopause height. In addition, the average occurrence frequencies of ISS and ice crystals on …
Comparing The Model-Simulated Global Warming Signal To Observations Using Empirical Estimates Of Unforced Noise, Patrick T. Brown, Wenhong Li, Eugene C. Cordero, Steven A. Mauget
Comparing The Model-Simulated Global Warming Signal To Observations Using Empirical Estimates Of Unforced Noise, Patrick T. Brown, Wenhong Li, Eugene C. Cordero, Steven A. Mauget
Faculty Publications, Meteorology and Climate Science
The comparison of observed global mean surface air temperature (GMT) change to the mean change simulated by climate models has received much public and scientific attention. For a given global warming signal produced by a climate model ensemble, there exists an envelope of GMT values representing the range of possible unforced states of the climate system (the Envelope of Unforced Noise; EUN). Typically, the EUN is derived from climate models themselves, but climate models might not accurately simulate the correct characteristics of unforced GMT variability. Here, we simulate a new, empirical, EUN that is based on instrumental and reconstructed surface …
Dust Deposition In The Eastern Indian Ocean: The Ocean Perspective From Antarctica To The Bay Of Bengal, Maxime Grand, Christopher Measures, Mariko Hatta, William Hiscock, Clifton Buck, William Landing
Dust Deposition In The Eastern Indian Ocean: The Ocean Perspective From Antarctica To The Bay Of Bengal, Maxime Grand, Christopher Measures, Mariko Hatta, William Hiscock, Clifton Buck, William Landing
Faculty Publications
Atmospheric deposition is an important but still poorly constrained source of trace micronutrients to the open ocean because of the dearth of in situ measurements of total deposition (i.e., wet + dry deposition) in remote regions. In this work, we discuss the upper ocean distribution of dissolved Fe and Al in the eastern Indian Ocean along a 95°E meridional transect spanning the Antarctic margin to the Bay of Bengal. We use the mixed layer concentration of dissolved Al in conjunction with empirical data in a simple steady state model to produce 75 estimates of total dust deposition that we compare …
Dissolved Fe And Al In The Upper 1000 M Of The Eastern Indian Ocean: A High‐Resolution Transect Along 95°E From The Antarctic Margin To The Bay Of Bengal, Maxime Grand, Christopher Measures, Mariko Hatta, William Hiscock, William Landing, Peter Morton, Clifton Buck, Pamela Barrett, Joseph Resing
Dissolved Fe And Al In The Upper 1000 M Of The Eastern Indian Ocean: A High‐Resolution Transect Along 95°E From The Antarctic Margin To The Bay Of Bengal, Maxime Grand, Christopher Measures, Mariko Hatta, William Hiscock, William Landing, Peter Morton, Clifton Buck, Pamela Barrett, Joseph Resing
Faculty Publications
A high‐resolution section of dissolved iron (dFe) and aluminum (dAl) was obtained along ~95°E in the upper 1000 m of the eastern Indian Ocean from the Antarctic margin (66°S) to the Bay of Bengal (18°N) during the U.S. Climate Variability and Predictability (CLIVAR) CO2 Repeat Hydrography I08S and I09N sections (February–April 2007). In the Southern Ocean, low concentrations of dAl (<1 n M) reflect the negligible dust inputs impacting the water masses subducted in the circumpolar domain. The low dAl concentrations characterizing the Southern Ocean terminate near 45°S, probably because of the advection of subtropical water masses that received dust and sedimentary inputs in their formation region. Our subsurface dFe data near the southern Kerguelen Plateau were significantly higher than historical observations in other Indian sectors of the Southern Ocean. We surmise that the offshore advection of dFe‐rich waters along the western flank of the southern Kerguelen plateau and enhanced vertical mixing could contribute to this elevated subsurface dFe inventory. Elevated subsurface particulate and dFe levels downstream of the northern Kerguelen Plateau may reflect long‐range lateral transport from the plateau's sediments and/or remineralization inputs. At the northern edge of the south Indian subtropical gyre, the deposition of Australian dust, possibly combined with the advection of dAl‐enriched waters from the Indonesian Throughflow, creates a region of elevated dAl in the upper 400 m but without a corresponding enrichment in dFe. In the northern Indian Ocean, the South Equatorial Current constitutes a remarkable biogeochemical front separating the oxygen‐rich and dFe‐poor subtropical gyre waters from the dFe‐rich and oxygen‐depleted waters of the northern Indian Ocean. By tracing the accumulation of macronutrients and dFe along the advective pathway of Indian Central Water, we show that the central waters of the northern Indian Ocean receive excess dFe in addition to that produced by remineralization inputs. The resuspension of shelf sediments and release of pore waters probably contribute to the elevated dFe and dAl levels observed below the highly stratified upper layers of the Bay of Bengal.
Cold Smoke: Smoke-Induced Density Currents Cause Unexpected Smoke Transport Near Large Wildfires, Neil Lareau, Craig Clements
Cold Smoke: Smoke-Induced Density Currents Cause Unexpected Smoke Transport Near Large Wildfires, Neil Lareau, Craig Clements
Faculty Publications, Meteorology and Climate Science
The first observations of smoke-induced density currents originating from large wildfires are presented. Using a novel mobile Doppler lidar and additional in situ measurements, we document a deep (~ 2 km) smoke-filled density current that propagates more than 25 km at speeds up to 4.5 m s−1 near a large forest fire in northern California. Based on these observations we show that the dynamics governing the spread of the smoke layer result from differential solar heating between the smoke-filled and smoke-free portions of the atmospheric boundary layer. A calculation of the theoretical density current speed agrees well with the observed …
Observations Of Fire-Induced Turbulence Regimes During Low-Intensity Wildland Fires In Forested Environments: Implications For Smoke Dispersion, Warren Heilman, Craig Clements, Daisuke Seto, Xindi Bian, Kenneth Clark, Nicholas Skowronski, John Hom
Observations Of Fire-Induced Turbulence Regimes During Low-Intensity Wildland Fires In Forested Environments: Implications For Smoke Dispersion, Warren Heilman, Craig Clements, Daisuke Seto, Xindi Bian, Kenneth Clark, Nicholas Skowronski, John Hom
Faculty Publications, Meteorology and Climate Science
Low-intensity wildland fires occurring beneath forest canopies can result in particularly adverse local air-quality conditions. Ambient and fire-induced turbulent circulations play a substantial role in the transport and dispersion of smoke during these fire events. Recent in situ measurements of fire–atmosphere interactions during low-intensity wildland fires have provided new insight into the structure of fire-induced turbulence regimes and how forest overstory vegetation can affect the horizontal and vertical dispersion of smoke. In this paper, we provide a summary of the key turbulence observations made during two low-intensity wildland fire events that occurred in the New Jersey Pine Barrens.