Physical Sciences and Mathematics Commons^™

Isotopic Signature Of Massive, Buried Ice In Eastern Taylor Valley, Antarctica: Implications For Its Origin, Christopher B. Gardner, Melisa A. Diaz, Devin F. Smith, Andrew G. Fountain, Joseph S. Levy, W. Berry Lyons

Geography Faculty Publications and Presentations

The coastal regions of the McMurdo Dry Valleys, Antarctica, contain deposits of the Ross Sea Drift, sedimentary material left from the Ross Sea ice sheet from the advance of the West Antarctic ice sheet during the Last Glacial Maximum. Much of this deposit is ice-cored, but data on the stable isotopic composition of water from this ice, which may contain a valuable climate archive, are sparse or incomplete. Widespread thermokarstic ground subsidence in this “coastal thaw zone” of the McMurdo Dry Valleys suggests that these potential records are rapidly being lost due to the melting of ground ice and permafrost. …

Historical Tsunami Observability For Izu–Bonin–Mariana Sources, Walter Szeliga, Rachelle Reisinger, Breanyn T. Macinnes

Geological Sciences Faculty Scholarship

The Izu–Bonin–Mariana Subduction System (IBM) is one of the longest subduction zones in the world with no instrumental history of shallow focus, great earthquakes (Mw > 8). Over the last 50 years, researchers have speculated on the reason for the absence of large magnitude, shallow seismicity on this plate interface, exploring factors from plate age to convergence rate. We approach the question from a different point of view: what if the IBM has hosted great earthquakes and no documentable evidence was left? To address the question of observability, we model expected tsunami wave heights from nine great earthquake scenarios on the …

Rapid Bacterial And Fungal Successional Dynamics In First Year After Chaparral Wildfire, M. Fabiola Pulido-Chavez, James W. J. Randolph, Cassandra A. Zalman, Loralee Larios, Peter M. Homyak, Sydney I. Glassman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The rise in wildfire frequency and severity across the globe has increased interest in secondary succession. However, despite the role of soil microbial communities in controlling biogeochemical cycling and their role in the regeneration of post-fire vegetation, the lack of measurements immediately post-fire and at high temporal resolution has limited understanding of microbial secondary succession. To fill this knowledge gap, we sampled soils at 17, 25, 34, 67, 95, 131, 187, 286, and 376 days after a southern California wildfire in fire-adapted chaparral shrublands. We assessed bacterial and fungal biomass with qPCR of 16S and 18S and richness and composition …

An Eolian Dust Origin For Clastic Fines Of Devono-Mississippian Mudrocks Of The Greater North American Midcontinent, Austin J. Mcglannan, Alicia Bonar, Lily Pfeifer, Sebastian Steinig, Paul Valdes, Steven Adams, David Duarte, Benmadi Milad, Andrew Cullen, Gerilyn S. Soreghan

School of Earth & Environment Faculty Scholarship

Upper Devonian and Lower–Middle Mississippian strata of the North American midcontinent are ubiquitously fine-grained and silt-rich, comprising both so-called shale as well as argillaceous limestone (or calcareous siltstone) that accumulated in the Laurentian epeiric sea. Although long recognized as recording marine deposition, the origin and transport of the fine-grained siliciclastic material in these units remains enigmatic because they do not connect to any proximal deltaic feeder systems. Here, we present new data on grain size, whole-rock geochemistry, mineralogy, and U-Pb detrital-zircon geochronology from units across Oklahoma; we then integrate these data with models of surface wind circulation, refined paleogeographic reconstructions, …

Equivalent Hazard Magnitude Scale, Yi Victor Wang, Antonia Sebastian

Institute for ECHO Articles and Research

Hazard magnitude scales are widely adopted to facilitate communication regarding hazard events and the corresponding decision making for emergency management. A hazard magnitude scale measures the strength of a hazard event considering the natural forcing phenomena and the severity of the event with respect to average entities at risk. However, existing hazard magnitude scales cannot be easily adapted for comparative analysis across different hazard types. Here, we propose an equivalent hazard magnitude scale to measure the hazard strength of an event across multiple types of hazards. We name the scale the Gardoni Scale after Professor Paolo Gardoni. We design the …

Surficial Geologic Map Of The Summit 7.5-Minute Quadrangle, Kentucky, Antonia E. Bottoms, Ann Hislop, Matthew A. Massey, Max Hammond Iii, Michelle Mchugh, Emily Morris

Report of Investigations--KGS

The Summit 7.5-minute quadrangle is located south of Louisville and west of Elizabethtown along the boundary between Hardin and Grayson Counties and within the Mississippian Plateau physiographic region (McDowell, 1986). Topography is characterized by the low relief Pennyroyal region that sits at elevations between 560 to 650 ft above sea level, the low relief Mammoth Cave plateau at elevations between 750 to 900 ft, and the steep Dripping Springs escarpment that separates the two plains. Moore (1964) mapped the bedrock geology of the quadrangle, which was later digitized by Conley (2002). Mississippian bedrock is exposed throughout the quadrangle and is …

Relative Importance Of Radar Variables For Nowcasting Heavy Rainfall: A Machine Learning Approach, Yi Victor Wang, Seung Hee Kim, Geunsu Lyu, Choeng-Lyong Lee, Gyuwon Lee, Ki-Hong Min, Menas C. Kafatos

Institute for ECHO Articles and Research

Highly short-term forecasting, or nowcasting, of heavy rainfall due to rapidly evolving mesoscale convective systems (MCSs) is particularly challenging for traditional numerical weather prediction models. To overcome such a challenge, a growing number of studies have shown significant advantages of using machine learning (ML) modeling techniques with remote sensing data, especially weather radar data, for high-resolution rainfall nowcasting. To improve ML model performance, it is essential first and foremost to quantify the importance of radar variables and identify pertinent predictors of rainfall that can also be associated with domain knowledge. In this study, a set of MCS types consisting of …

Phase I Activities Of The Earth Mapping Resources Initiative (Earth Mri) In The Western Kentucky Fluorspar District, Georgina Lukoczki, Craig Dietsch, John B. Hickman, Emily Morris, Douglas C. Curl, Carrie Pulliam, Stephanie Vicroy, William M. Andrews Jr.

Report of Investigations--KGS

The Western Kentucky Fluorspar District (WKFD), which comprises the Kentucky portion of the Illinois–Kentucky Fluorspar District, is well known for the occurrence of strategically important critical mineral resources, such as fluorite (fluorspar) and rare earth elements (REEs). Due to technological advances, demand has increased for critical minerals used in cell phones, magnets in wind turbines, batteries for electric vehicles, smart weapons, and other devices and systems. The overall objective of the Earth Mapping Resources Initiative (Earth MRI) program, directed by the U.S. Geological Survey (USGS), is to gather information that will help better understand the distribution of critical minerals in …

Uncertainty Of Icesat-2 Atl06- And Atl08-Derived Snow Depths For Glacierized And Vegetated Mountain Regions, Ellyn M. Enderlin, Colten M. Elkin, Madeline Gendreau, H.P. Marshall, Shad O'Neel, Christopher Mcneil, Caitlyn Florentine, Louis Sass

Geosciences Faculty Publications and Presentations

Seasonal snow melt dominates the hydrologic budget across a large portion of the globe. Snow accumulation and melt vary over a broad range of spatial scales, preventing accurate extrapolation of sparse in situ observations to watershed scales. The lidar onboard the Ice, Cloud, and land Elevation, Satellite (ICESat-2) was designed for precise mapping of ice sheets and sea ice, and here we assess the feasibility of snow depth-mapping using ICESat-2 data in more complex and rugged mountain landscapes. We explore the utility of ATL08 Land and Vegetation Height and ATL06 Land Ice Height differencing from reference elevation datasets in two …

Future Colorado River Basin Drought And Surplus, Rama Bedri, Thomas Piechota

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Historical and future drought and surplus periods in the Colorado River basin are evaluated based on eight climate scenarios. Unimpaired streamflow from 17 stations in the Colorado River are evaluated based on U.S. Geological Survey, Bureau of Reclamation, and Coupled Modeled Intercomparison Projection 5 downscaled data from 1950–2099. Representative Concentration Pathway (RCP) 4.5 and 8.5 emission scenarios are considered for four climate models (HadGEM2-ES, CNRM-CM5, CanESM2, MI-ROC5). Drought (surplus) quantities, magnitudes, severities, and water year flows are compared for the historical and future periods. Results indicate that there is a significant difference between the historical record and future projections. The …

On The Relative Importance Of Offshelf/Onshelf Drivers Of Variability In Mcdw Inventory On The Amundsen Shelf, Antarctica, Pierre St-Laurent, S. E. Stammerjohn, T. Maksym, R. M. Sherrell

Presentations

Ice shelves in the Amundsen Sea (west Antarctica) are melting rapidly and may raise global sea levels substantially over the coming century through reduced buttressing. The high basal melt rates are associated with the presence of warm modified Circumpolar Deep Water (mCDW) that intrudes across the continental shelf and melts the floating portion of the ice sheet from its base near the grounding zone. How much mCDW is present on the continental shelf (its volume inventory) is thus thought to be a key proxy for the year-to-year variability in ice shelf melt rates. Over the past decade, the literature has …

On The Use Of Machine Learning For Causal Inference In Extreme Weather Events, Yuzhe Wang

Discovery Undergraduate Interdisciplinary Research Internship

Machine learning has become a helpful tool for analyzing data, and causal Inference is a powerful method in machine learning that can be used to determine the causal relationship in data. In atmospheric and climate science, this technology can also be applied to predicting extreme weather events. One of the causal inference models is Granger causality, which is used in this project. Granger causality is a statistical test for identifying whether one time series is helpful in forecasting the other time series. In granger causality, if a variable X granger-causes Y: it means that by using all information without …

Diversifying And Perennializing Plants In Agroecosystems Alters Retention Of New C And N From Crop Residues, Marshall D. Mcdaniel, Jeffrey A. Bird, Jennifer Pett-Ridge, Erika Marin-Spiotta, Tom M. Schmidt, A. Stuart Grandy

Faculty Publications

Managing soils to retain new plant inputs is key to moving toward a sustainable and regenerative agriculture. Management practices, like diversifying and perennializing agroecosystems, may affect the decomposer organisms that regulate how new residue is converted to persistent soil organic matter. Here we tested whether 12 years of diversifying/perennializing plants in agroecosystems through extended rotations or grassland restoration would decrease losses of new plant residue inputs and, thus, increase retention of carbon (C) and nitrogen (N) in soil. We tracked dual-labeled (13C and 15N), isotopically enriched wheat (Triticum aestivum) residue in situ for 2 years as it decomposed in three …

Sturgeon Chub Distributional Patterns And Habitat Use And Benthic Fish Assemblage Structure In Missouri River Tributaries Of South Dakota, Mitchell R. Magruder

School of Natural Resources: Dissertations, Theses, and Student Research

Native species of the Missouri River drainage inhabiting benthic habitats dominate state and federal lists of species at risk. Sicklefin Chub Macrhybopsis meeki and Sturgeon Chub Macrhybopsis gelida are two native Missouri River benthic minnows that are currently under review for federal listing under the Endangered Species Act (ESA) due to extensive population declines and local extirpations within their native range. Substantial alterations to the Missouri River threaten Macrhybopsis spp. and other benthic fishes; however, large, less impacted tributaries in South Dakota may act as refugia for native species. The extent of Sicklefin Chub and Sturgeon Chub populations is largely …

Human And Hydrologic Influences On Nebraska's Endangered Rainwater Basin Wetlands, Sarah Thompson

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Over half of wetlands in North America have been lost or degraded. Rainwater Basin (RWB) wetlands, located in south-central Nebraska, are a primary example of such loss; an estimated 90% have been destroyed by land conversion for agriculture. Remaining RWB wetlands are often embedded in row-crop fields, where they are threatened by altered surface water runoff flow, drainage features, and excess sediment inputs. Efforts at the state and federal level have been made to preserve this wetland complex due to the critical stopover habitat these wetlands provide for migratory birds. Land managers work to maintain sufficient water levels during migratory …

The North Platte River Valley: The Intersectionality Between Water Quality And People, Anni Poetzl

School of Natural Resources: Dissertations, Theses, and Student Research

The North Platte River (NPR) Valley of western Nebraska is a semi-arid watershed with row crop production, livestock production, and urban land use activity and has a population of diverse stakeholders. These land use activities contribute to the enrichment of surface waters, such as streams, which can affect human and ecosystem health, as well as economic development and recreational activities. The project objectives are to: (1) quantify the movement of dissolved inorganic nutrients from the land within the NPR Valley to the NPR via tributaries and canals, (2) identify spatiotemporal variability of nutrient limitation of periphyton growth within the NPR, …

Earlier Snowmelt May Lead To Late Season Declines In Plant Productivity And Carbon Sequestration In Arctic Tundra Ecosystems, Donatella Zona, Peter M. Lafleur, Koen Hufkens, Barbara Bailey, Beniamino Gioli, George Burba, Jordan P. Goodrich, Anna K. Liljedahl, Eugénie S. Euskirchen, Jennifer D. Watts, Mary Farina, John S. Kimball, Martin Heimann, Mathias Göckede, Martijn Pallandt, Torben R. Christensen, Mikhail Mastepanov, Efrén López-Blanco, Marcin Jackowicz-Korczynski, Albertus J. Dolman, Luca Belelli Marchesini, Roisin Commane, Steven C. Wofsy, Charles E. Miller, David A. Lipson, Josh Hashemi, Kyle A. Arndt, Lars Kutzbach, David Holl, Julia Boike, Christian Wille, Torsten Sachs, Aram Kalhori, Xia Song

Daugherty Water for Food Global Institute: Faculty Publications

Arctic warming is affecting snow cover and soil hydrology, with consequences for carbon sequestration in tundra ecosystems. The scarcity of observations in the Arctic has limited our understanding of the impact of covarying environmental drivers on the carbon balance of tundra ecosystems. In this study, we address some of these uncertainties through a novel record of 119 site-years of summer data from eddy covariance towers representing dominant tundra vegetation types located on continuous permafrost in the Arctic. Here we found that earlier snowmelt was associated with more tundra net CO2 sequestration and higher gross primary productivity (GPP) only in June …

The Formation Of The 8˚20’ N Seamount Chain, East Pacific Rise, Dorsey Wanless

Geosciences Faculty Publications and Presentations

Near-axis seamounts provide a unique setting to investigate three-dimensional mantle processes associated with the formation of new oceanic crust and lithosphere. Here, we investigate the characteristics and evolution of the 8˚20’N Seamount Chain, a lineament of seamounts that extends ~ 175 km west of the East Pacific Rise (EPR) axis, just north of the fracture zone of the Siqueiros Transform Fault. Shipboard gravity, magnetic, and bathymetric data acquired in 2016 are utilized to constrain models of seamount emplacement and evolution. Geophysical observations indicate that these seamounts formed during four distinct episodes of volcanism coinciding with changes in regional plate motion …

Us Scientific Leadership Addressing Energy, Ecosystems, Climate, And Sustainable Prosperity: Report In Brief From The Berac Subcommittee On International Benchmarking, Maureen Mccann, Patrick Reed, Ana Alonso, Ludmilla Aristilde, Massie S. Ballon, Crysten Blaby, Allison A. Campbell, Kenneth James Davis, Brian H. Davison, Ben Evans, Robert F. Fischetti, Serita D. Frey, Ann M. Fridlind, Efi Foufoula-Georgiou, Ramon Gonzalez, Michael N. Gooseff, Nathan Hillson, Janet Jansson, Klaus Keller, Markus Kleber, Costas Maranas, Gerald A. Meehl, Himadri Pakrasi, Jennifer Pett-Ridge, Kristala Prather, Johannes Quaas, G. Philip Robertson, Alistair Rogers, Tim Scheibe, Thomas R. Schneider, Gary Stacey, Margaret S. Torn, Kerstin Kleese Van Dam, Detlef Vuuren, John Weyant, Stan Wullschleger, Shaocheng Xie, Seung Yon (Sue) Rhee, Huimin Zhao

Faculty Publications

This document presents the subcommittee’s overarching and domain-specific findings and recommendations for the next decade, identified by consensus across the full BERAC subcommittee and experts interviewed for this assessment.

Predictions And Drivers Of Sub-Reach-Scale Annual Streamflow Permanence For The Upper Missouri River Basin: 1989–2018, Kendra E. Kaiser

Geosciences Faculty Publications and Presentations

The presence of year-round surface water in streams (i.e., streamflow permanence) is an important factor for identifying aquatic habitat availability, determining the regulatory status of streams, managing land use change, allocating water resources, and designing scientific studies. However, accurate, high resolution, and dynamic prediction of streamflow permanence that accounts for year-to-year variability at a regional extent is a major gap in modeling capability. Herein, we expand and adapt the U.S. Geological Survey (USGS) PRObability of Streamflow PERmanence (PROSPER) model from its original implementation in the Pacific Northwest (PROSPER_PNW) to the upper Missouri River basin (PROSPER_UM), a …

Statistical Analysis Of Aquifer Hydraulic Properties By A Continuous Pumping Tomography Test: Application To The Boise Hydrogeophysical Research Site, Kan Bun Cheng, Gedeon Dagan, Warren Barrash, Michael Cardiff, Avinoam Rabinovich

Geosciences Faculty Publications and Presentations

Characterizing aquifer heterogeneity is paramount for accurate flow and transport modeling. In this work, we present a new approach for statistical analysis of hydraulic properties in continuous pumping tomography tests of a phreatic aquifer. The method entails determining equivalent hydraulic conductivity (K_eq), specific storage (S_s,eq), and specific yield (S_y,eq) at many locations in the field and then calculating statistical moments of the equivalent properties, assuming they are random space variables. Equivalent properties are defined as the ones pertinent to a homogeneous aquifer for which the head time …

Carbon Cycling And Critical Zone Dynamics In An Urbanized Karst Groundwater System, Amy Hourigan

Masters Theses & Specialist Projects

Increasing atmospheric CO₂ concentrations are correlated to rising global temperatures. Investigating the cumulative global carbon cycling processes is important to understand and quantify the global carbon cycle. By investigating basic geochemical parameters, EpCO₂, DIC, and δ¹³C_DIC, at four sites along Lost River Cave (LRC), in Bowling Green, Kentucky, concentrations, fluxes and sources of C dissolved in groundwater were determined. Urban karst groundwater systems, compared to more natural karst landscapes, typically exhibit widespread impervious, heat-absorbing surfaces, urban heat island effects, and increased anthropogenic groundwater inputs and localized CO₂ emissions. Carbonate hydrogeochemical …

Tonga Volcanic Eruption And Tsunami, January 2022: Globally The Most Significant Opportunity To Observe An Explosive And Tsunamigenic Submarine Eruption Since Ad 1883 Krakatau, James P. Terry, James Goff, Nigel Winspear, Vena Pearl Bongolan, Scott Fisher

All Works

January 2022 witnessed the violent eruption of Hunga Tonga–Hunga Haʻapai submarine volcano in the South Pacific. With a volcanic explosivity index possibly equivalent to VEI 5, this represents the largest seaborne eruption for nearly one and a half centuries since Indonesia’s cataclysmic explosion of Krakatau in AD 1883. The Tongan eruption remarkably produced ocean-wide tsunamis, never documented before in the Pacific instrumental record. Volcanically generated tsunamis have been referred to as a ‘blind spot’ in our understanding of tsunami hazards, particularly in the Pacific Ocean. This event therefore presents a unique opportunity for investigating the multiple processes contributing to volcanic …

One Health In Action: Flea Control And Interpretative Education At Badlands National Park, David Eads, Lindsey Buehler, Anne Esbenshade, Jason Fly, Evan Miller, Holly Redmond, Emily Ritter, National Park Service, Sasha Wittmann, Paul Roghair, Eddie Childers

United States Geological Survey: Staff Publications

No abstract provided.

Using Landsat Satellite Imagery To Estimate Groundcover In The Grainbelt Of Western Australia, Justin Laycock, Nick Middleton, Karen Holmes

Resource management technical reports

Maintaining vegetative groundcover is an important component of sustainable agricultural systems and plays a critical function for soil and land conservation in Western Australia’s (WA) grainbelt (the south-west cropping region). This report describes how satellite imagery can be used to quantitatively and objectively estimate total vegetative groundcover, both in near real time and historically across large areas. We used the Landsat seasonal fractional groundcover products developed by the Joint Remote Sensing Research Program from the extensive archive of Landsat imagery. These products provide an estimate of the percentage of green vegetation, non-green vegetation and bare soil for each 30 m …

Groundwater Modelling Of The Newman Area For Managed Aquifer Recharge Assessment, Wolfgang Schmid, Rodrigo Rojas, Michael J. Donn, Christopher Schelfhout Dr, Mathias Raiber, Olga Barron

Natural resources commissioned reports

This report contributes to the Transforming Agriculture in the Pilbara (TAP) initiative that has been developed to undertake the detailed studies in the Pilbara to bring suitable medium to large scale irrigation land to market for private investment. The research objective was to explore opportunities for irrigated agriculture north of Newman (Eastern Pilbara), deploying managed aquifer recharge (MAR) to secure water for irrigation. MAR source water identified was from mine dewatering surplus, generated from the large BHP Iron Ore operation in the Newman region. The objectives of this report were to:

• conceptualise the groundwater system and associated processes in the …

Physical Controls On The Hydrology Of Perennially Ice-Covered Lakes, Taylor Valley, Antarctica (1996-2013), J. M. Cross, Andrew G. Fountain, M. J. Hoffman, M. K. Obryk

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys, Antarctica, are a polar desert populated with numerous closed-watershed, perennially ice-covered lakes primarily fed by glacial melt. Lake levels have varied by as much as 8 m since 1972 and are currently rising after a decade of decreasing. Precipitation falls as snow, so lake hydrology is dominated by energy available to melt glacier ice and to sublimate lake ice. To understand the energy and hydrologic controls on lake level changes and to explain the variability between neighboring lakes, only a few kilometers apart, we model the hydrology for the three largest lakes in Taylor Valley. We …

Substrate Availability And Not Thermal Acclimation Controls Microbial Temperature Sensitivity Response To Long-Term Warming, Luiz A. Domeignoz-Horta, Grace Pold, Hailey Erb, David Sebag, Eric Verrecchia, Trent Northen, Katherine Louie, Emiley Eloe-Fadrosh, Christa Pennacchio, Melissa A. Knorr, Serita D. Frey, Jerry M. Melillo, Kristen M. Deangelis

Faculty Publications

Microbes are responsible for cycling carbon (C) through soils, and predicted changes in soil C stocks under climate change are highly sensitive to shifts in the mechanisms assumed to control the microbial physiological response to warming. Two mechanisms have been suggested to explain the long-term warming impact on microbial physiology: microbial thermal acclimation and changes in the quantity and quality of substrates available for microbial metabolism. Yet studies disentangling these two mechanisms are lacking. To resolve the drivers of changes in microbial physiology in response to long-term warming, we sampled soils from 13- and 28-year-old soil warming experiments in different …

Spinosaurus Is Not An Aquatic Dinosaur, Paul C. Sereno, Nathan Myhrvold, Donald M. Henderson, Frank E. Fish, Stephanie L. Baumgart, Tyler M. Keillor, Kiersten K. Formoso, Lauren L. Conroy

Biology Faculty Publications

A predominantly fish-eating diet was envisioned for the sail-backed theropod dinosaur Spinosaurus aegyptiacus when its elongate jaws with subconical teeth were unearthed a century ago in Egypt. Recent discovery of the high-spined tail of that skeleton, however, led to a bolder conjecture that S. aegyptiacus was the first fully aquatic dinosaur. The "aquatic hypothesis' posits that S. aegyptiacus was a slow quadruped on land but a capable pursuit predator in coastal waters, powered by an expanded tail. We test these functional claims with skeletal and flesh models of S. aegyptiacus. We assembled a CT- based skeletal reconstruction based on the …

Increased Aerosols Can Reverse Twomey Effect In Water Clouds Through Radiative Pathway, Pradeep Khatri, Tadahiro Hayasaka, Brent N. Holben, Ramesh P. Singh, Husi Letu, Sachchida N. Tripathi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aerosols play important roles in modulations of cloud properties and hydrological cycle by decreasing the size of cloud droplets with the increase of aerosols under the condition of fixed liquid water path, which is known as the first aerosol indirect effect or Twomey-effect or microphysical effect. Using high-quality aerosol data from surface observations and statistically decoupling the influence of meteorological factors, we show that highly loaded aerosols can counter this microphysical effect through the radiative effect to result both the decrease and increase of cloud droplet size depending on liquid water path in water clouds. The radiative effect due to …