We present a neural network (NN) based algorithm for the retrieval of cloud and aerosol properties from above cloud aerosol (ACA) scenes. The large state space explored in ACA scenes causes traditional retrieval approaches slow and complicated. This is especially true for optimal inversion retrieval approaches, where a growth in the number of dependent variables can drastically complicate and slow the retrieval search. Our NN retrieval is applied to data from the airborne Research Scanning Polarimeter (RSP), which measures both polarized and total reflectance in the spectral range of 410 to 2260 nm, scanning along the flight track at ~150 viewing zenith angles spanning the angular range between -60˚ to 60˚. We apply this algorithm to field campaign data from the ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) 2016 and 2017 campaigns and compare to results obtained from other algorithms.

New 230Th/238U ages for precisely leveled fossil corals from Araki Island, Vanuatu, generally corroborate MIS 3 and 4 paleosealevel estimates from the Huon Peninsula (HP), Papua New Guinea. Corals have been essential for paleosea-level reconstructions and their timing because they provide such precise U-series dates. However, paleosea-level estimates from uplifted corals rely on inferring tectonic uplift rates in order to subtract them from coral elevations. Uplifted coral reefs at central Varnuatu and Western Solomons exemplify the extremely abrupt tectonic rate changes that forearcs can undergo. If uplift rate changes are not detected and taken into account then paleosea level estimates could be wrong by tens of meters. Araki Island, located 2500 km and two plates away from the Huon Peninsula is tectonically independent. Araki should share a similar paleosea level history with HP, including Global Isostatic Adjustments, and other water-loading influences, but should be tectonically different. Assumptions similar to those used to infer HP sea-level estimates are applied for the Araki mid-Holocene, MIS 5c, and MIS 5e paleosealevels in order to constrain MIS 3 and 4 paleosea levels. Before and during MIS 5e (~130-120 ka) until MIS 5c (~106 ka) Araki subsided at ~3 mm/yr. At or soon after 106 ka Araki abruptly began uplifting at a mean rate of ~1.65 mm/yr. This ~1.65 mm/yr mean uplift rate appears to have prevailed until ~25-30 ka after which uplift accelerated to a mean rate of ~4.6 mm/yr. These uplift rates imply MIS 3 and 4 paleosea levels very similar to those inferred from the HP reef terraces of similar ages. The abrupt changes in vertical tectonics that our coral ages and elevations imply for Araki Island offer insightsregarding the remarkably rapid tectonic variability and possible mechanisms that control convergent margin tectonics as well as the challenges involved in using the data for paleosea level reconstructions.

The highlands of Ethiopia are a densely populated, agriculturally active region characterized by strong topographic contrasts. These contrasts have significant implications for agricultural productivity and for vulnerability to climate variability and change. These differing vulnerabilities are evident in analyses of economic and health outcomes over time, and they were on stark display during the major El Niño drought of 2015. To provide meaningful analysis of climate vulnerability in this region and, ultimately, to support climate resilience strategies, it is necessary to account for this topographic diversity. Recognizing this, the Government of Ethiopia has applied an “adaptation zone” approach to climate change planning, in which adaptation zones are defined in large part by agroecology. Here, we present results of studies we have performed in the Ethiopian Highlands over the past decade in which agroecosystems were applied as a lens for analyzing hydrology, land management and change, agricultural production, and nutrition under climate variability. This approach has informed a number of active development initiatives in the region, including protection of high elevation zones, farmer-led initiatives on soil and water management, and introduction of new cropping strategies. Looking forward, climate projections at the scale of the agroecosystem point to emerging risks and opportunities for resilient agricultural development in the region.

The Council on Undergraduate Research (CUR) is engaged in several formal and informal partnerships within the Geosciences community, and is vital for all faculty, staff, and students involved with undergraduate research. CUR is structured into thirteen (13) separate divisions, of which one of the most active is the Geosciences Division, affectionately known as GeoCUR. CUR has a formal Memorandum of Understanding (MOU) with the American Geophysical Union (AGU) to foster collaboration and mutual benefit. CUR is also an Associated Society of the Geological Society of America (GSA), and a Member Society of the American Geosciences Institute (AGI). Within CUR, the GeoCUR regularly sponsors technical sessions, awards, poster sessions, and/or workshops at the AGU and GSA annual meetings, and an exhibit booth at the GSA Annual Meeting to raise awareness of CUR and the benefits of undergraduate research (UR). For the first time ever, GeoCUR will have an exhibit booth at the AGU meeting in 2018, and will be actively recruiting and engaging AGU meeting attendees. CUR advocacy is expanded when CUR staff and members participate in GSA Associated Societies and AGI Member Societies meetings. CUR is the voice for the UR community, and has worked with both AGU and other scientific societies to advise and educate legislators and federal agency representatives of the importance of UR, and also the continued support of geoscience research priorities, such as climate change research. One of the CUR’s most effective advocacy avenues is its annual Posters on the Hill event, now entering its 23rd year. EvaluateUR is an important outgrowth of CUR partnerships, and illustrates CUR’s important role in UR assessment. EvaluateUR is an evidence-based model for improving UR student outcomes, funded by NSF WIDER, and partnering SUNY Buffalo State, NAGT/SERC and CUR. EvaluateUR started at SUNY Buffalo State, has expanded to a diverse array of institutions, and is actively seeking new potential partners.

Clear air turbulence (CAT) is a serious threat for civil aviation flights. In the years 2009 through 2015, with the support of the European Commission, as a part of the 7th Framework Program, the DELICAT project (DEmonstration of LIdar based Clear Air Turbulence detection) was implemented. In this project, an air-borne lidar was developed and built for an early detection of CAT. In August 2013, flight tests of the lidar were carried out. During the experiments, a large unique data set was collected; a copy of the data set is in the possession of the Obukhov Institute of Atmospheric Physics of Russian Academy of Sciences (IAP RAS). In the proposed project, we propose solving the following problems. We will develop a numerical model of the laser sounding of CAT, considering the effect of the laser beam propagation in a random medium, as well as the aerosol (Mie) and molecular (Rayleigh) scattering. The analysis of the existing observations indicates that, in most cases, the multiple scattering effects are negligible. The will allow us to develop the model on the basis of the multiple phase screen method. This model will produce realizations of the random signal for specific realization of the random refractivity and aerosol distribution fields. A modification of the multiple phase screen method will allow modeling a diverging laser beam. This will also allow modeling of the back-scattering enhancement (BSE). By varying the aerosol composition, it will be possible to model different degree of correlation and intensity ratio in co- and cross-polarization channels. The model of the laser sounding of CAT will help answering the question, whether aerosol is an impeding factor when using the BSE effect. We will develop a realistic model of the observation geometry variations. We will perform the primary processing of the whole available data set of the DELICAT observations. This will allow us to estimate the statistical properties of the measurement noise. We will analyze the DELICAT observations. We will fit the model parameters in order to reproduce, as close as possible, the statistical properties of the observations. This will help answering the questions, how accurately and timely it is possible to detect CAT parameters using two types of lidar systems: 1) system with two polarization channels, and 2) system based on the BSE effect.

As sources of fresh water and critical components of the global climate system, terrestrial glaciers are important features to monitor, particularly in light of anthropogenic climate change. Remote sensing techniques are being increasingly used to gather information on Earth’s shrinking complex glacial terrains. However, these methods possess critical challenges, including capturing firn dynamics and the presence of ice lenses. Meltwater percolation and retention, as well as thermodynamic effects on snow and firn density can complicate the relationship between surface height and mass balance changes; lowering of the glacier surface may masquerade as a mass change as detected by remote sensing technologies. The St. Elias Mountains, straddling the border between Yukon Territory, Canada and Alaska, USA, are home to extensive icefields. While numerous mass balance studies have been conducted in this region using remote sensing, there is a significant lack of in situ measurements of accumulation zone processes and firn properties. Our research examines refrozen ice layers and firn densification processes in the accumulation zone of Kaskawulsh Glacier in the St. Elias Mountains. In spring 2018, we extracted two firn cores (20 m and 35 m) from the study area and conducted a snow stratigraphy and ice lens survey on both core sections. After subsampling and melting the cores, we analyzed major ion and isotope chronology to identify extreme meltwater percolation and refreezing events, both of which critically affect firn density. The snow stratigraphy analysis from both of the cores showed numerous refrozen ice layers, indicating surface melt and refreezing processes in the accumulation zone. Preliminary results from isotope chronology analysis reveal a wash-out of the glaciochemical pattern in the 35 m and the 20 m ice core at 15 m depth, thus indicating severe surface warming events and subsequent changes in the density of the firn. This may indicate errors in the assumed density of the accumulation zone snow and firn when using remote sensing technologies to infer mass balance of Kaskawulsh Glacier.

In recent years, many researchers and advocates have noted the potential of religious groups and institutions to leverage their significant influence in favor of addressing environmental challenges. However, in the United States, many scientists struggle to communicate the implications of their work on climate change with faith communities who may be skeptical of both climate science and scientists. Recent polls from the Pew Research Center show that white evangelical Protestants are the least likely to believe climate change is caused by human activity and the most likely to assert that there is no solid scientific support for a changing climate. However, the full picture is more nuanced than can be captured in a news headline or polling survey, and evangelical Christiantiy is a diverse movement that is also found at the forefront of enviornmental and climate science and action. Drawing on more than six years of experience working on climate science communication and climate action solutions among fellow evangelicals in the United States, this presentation highlights best practices for communicating climate science to faith communities. Showcasing examples of work advanced through the Evangelical Environmental Network, Young Evangelicals for Climate Action, and PBS Global Weirding series with Dr. Katharine Hayhoe, I present a hopeful view of efforts to communicate climate change in a way that intentionally and genuinely connects with people's values, and ultimately motivates action. Additionally, this presentation discusses the challenges of and opportunities for engaging communities of faith as scientists with a different or no faith affiliation.

Channels and the water they convey control the spatial extent of aquatic ecosystems and the evolution of landscapes. Over geologic time scales (millions of years), flow rates have varied with changes in climate, glacial extent and tectonics; however, over shorter time scales, flow rates have remained stable enough to permit the establishment of unique ecosystems that depend on and interact with specific flow and sediment transport regimes. On the Olympic Peninsula, that relative stability was altered when humans converted vast areas of old-growth forest to tree plantations during the 20th century; however, because of the remote location and unstable nature of the channels affected by the tree farms, exactly how stream flow has changed is unknown. This study presents preliminary flow observations in the Olympic Experimental State Forest (OESF), a 110,000 ha block of public land on the west side of the Olympic Peninsula that is presently being managed for both timber and ecosystem values. Through repeat flow measurements and channel surveys and the installation of pressure transducers and staff gages, we are developing a long-term record of flow in small, (basin area 50 to 700 ha) step-pool to cascade channels that transport pulses of sediment and violently swing between low and high flows. Preliminary flow observations indicate that the geologic setting of the basin plays a large role in hydrograph characteristics and that picking out a vegetation signal in the flow record may be difficult. Nonetheless, the long-term goal of these observations is to quantify flow trends and help humans (The Washington State Department of Natural Resources) better understand how past and present tree harvests on the Olympic Peninsula may be altering natural hydrologic and geomorphic processes. Monitoring techniques we are using to measure flow in these small, dynamic streams, including the use of BaRatin (Le Coz et al., 2013) to develop rating curves, are presented. Future monitoring goals and plans to use the flow records for geomorphic and hydrologic modeling studies are also discussed.

Fronts, at both mesoscale and submesoscales, are generally hypothesized to play a significant role in mediating the transfer of tracers from the surface boundary layer into the interior. With the advent of computational capabilities numerous high resolution modeling studies have shown the enhancement of of vertical velocities with increasing horizontal resolution. In a carefully designed setup of an idealized channel partially blocked by meridional topography and forced by steady forcing, idealization of the Antarctic Circumpolar Current, we vary the horizontal resolution as the control parameter, and analyze the impact of enhanced vertical velocities on tracer subduction. It is found that the submesoscale-permitting simulations flux far more tracer downward than the lower resolution simulations, the 1km simulation takes up 50\% more tracer compared to the 20km simulation, despite the increased restratifying influence of the resolved submesoscale processes. A spectral decomposition of the flow and fluxes illuminated the relative importance of scales, and the inefficiency of inertia-gravity waves in influencing tracer transport. To further understand the physical dynamics in these simulations we diagnosed how energy was being transferred between the mean and eddy kinetic and potential energy reservoirs (Lorenz energy cycles), and if changing the resolution influenced this exchange. In particular we focussed on separating the dynamics of the energy cycles that are active in the interior of the water column and those that are trapped near the surface. We also analyzed the inter-lengthscale exchange of energy to understand the detailed spectral dynamics of the turbulence that is resolved. Lastly, and probably most relevant to SWOT, we looked at the energy budgets in terms of velocity and pressure structure functions, to assess the potential for the future SWOT mission to directly measure the inter-scale energy transfers at the ocean surface.

The Global Learning and Observations to Benefit the Environment (GLOBE) Program is an international science and education program that connects a network of communities around the world and gives them the opportunity to participate in data collection and the scientific process, and contribute meaningfully to our understanding of the Earth system and global environment. GLOBE hosts the GLOBE International STEM Network (GISN), which is an international network of STEM professionals that work with GLOBE students, teachers, and other STEM professionals around the world. Members of the GISN may mentor students and teachers, collaborate on scientific research, use GLOBE data in their research, judge student research projects, and write blogs for the GLOBE website, among other things. In January 2018, the GISN, which was previously only open to graduate students and seasoned STEM professionals, was expanded to include “Early Career STEM Professionals” which includes upper-level undergraduates or master’s students pursuing a degree in a STEM field or recent graduates working in STEM fields but have less than five years’ experience. Goals for expanding the the GISN include granting early career professionals a chance to establish ties with the next generation of STEM professionals, connecting early career professionals and students with potential mentors and collaborators, and allowing early career professionals and students to explore what a career in a STEM field can look like. All GISN members will benefit from an increase in the number of members as well as an increase in the numbers of members who have more flexibility in terms of time and finances. As well, it is another opportunity for GLOBE to engage with alumni of the program who have continued a career in STEM. Unlike other ECS networks, the GISN does not separate the ECS’ out from the other members so all members have equal access to resources and each other. Since opening up the GISN in January, 17 Early Career STEM Professionals representing 5 of our 6 regions (Africa, Asia and the Pacific, Europe and Eurasia, Latin America and the Caribbean, and North America, but not Near East and North Africa) have joined the network bringing total membership to 421 members.

Ash-producing volcanic eruptions are a major natural hazard and the magnitude of the explosivity of these eruptions have been indicated for decades by a semi-quantitative “Volcanic Explosivity Index (VEI)” based on a number of interdependent factors, (eruption duration, volume of ejected material, eruptive column height, tropospheric and stratospheric injection, and qualitative descriptors). We present a simple empirical formulation for a fully quantitative VEI (𝑉𝐸𝐼Hc), based solely on eruption column height. This method directly translates the height of the eruption column into VEI, a useful formulation for immediate understanding of the explosivity of eruptions as they are taking place. This new scale is calibrated for convenience and familiarity to span the same range of values as the existing, semi-quantitative, VEI scale. In addition to being a simple and quantitative approach, this new method, translating column height directly into VEI, has the advantage of being calculated in real time during an eruption. This will improve immediate response by aviation, hazard management, and others to mitigate societal impact of hazardous eruptions.

Hydro climate services, such as early warning systems and monitoring and forecasting services for floods and droughts, are required to deal with climate risk management and adaptation. Those tools also contribute to achieving international goals and commitments such as Sustainable Development Goals (SDGs), the Paris Agreement and the Sendai Framework for Disaster Risk Reductions. Recognizing these needs, UNESCO’s International Hydrological Programme (IHP) has fostered the creation and application of many such products in recent years. This has been accomplished through unique formal and informal partnerships among IHP programs, such as the Global Network on Water and Development Information for Arid Lands (G-WADI) and the International Flood Initiative (IFI); UNESCO regional and country offices in Africa, Latin America and Asia; university engineering and hydrology departments; and UNESCO’s network of affiliated (“category 2”) centers, such as the International Center for Integrated Water Resources Management (ICIWaRM) and the International Centre for Water Hazard and Risk Management (ICHARM). The presentation will include an overview of the products, tools and services developed through these collaborations among IHP and its “water family” and their effectiveness in providing such services to Member States.

A careful characterization of moisture fluxes and saturation-ratio statistics in atmospheric convection is significant for cloud microphysical processes and dynamics. The saturation-ratio of water vapor is defined as the ratio of actual water vapor pressure and its equilibrium value at a given air temperature. Therefore, it is a function of two scalars (water vapor and temperature) and is coupled through the nonlinear Clausius-Clapeyron equation. Participation of both scalar fields in the convection process and the nonlinear coupling of both scalars in saturation-ratio make this problem more complex, as compared to its dry-convection counterpart. We have explored heat and water vapor fluxes and saturation-ratio statistic in the moist Rayleigh-Bénard convection case, using the one-dimensional-turbulence (ODT) model developed by Wunsch et al. JFM 2005. This idealized small-scale simulation is a step toward understanding the full atmospheric convection problem at a more fundamental level. We have obtained the thermal and moisture fluxes as a function of the non-dimensional buoyancy parameter, also known as moist Rayleigh number, and compared it with the scaling relations. Moreover, we have examined the mean and variance profiles of saturation-ratio, and analyzed the different contributing terms for saturation-ratio fluctuations. Based on the scaling analysis, a simplified relation between saturation-ratio variance and moist Rayleigh number has been derived and compared with the simulation results. Additionally, we found that different values of water vapor and thermal diffusivities make the saturation-ratio pdf broader than the case when they are considered equal.

The spatio-temporal variability of river processes is governed by the balance between basin scale sediment supply and channel transport capacity. This balance is being altered by rampant sediment mining from the rivers which results in channel alteration and loss of physical habitat. The sediment mining guidelines are mostly based on empirical approaches and do not consider the spatio-temporal variability of river processes. This study includes hydrologic and geomorphic analysis to understand sediment dynamics and to suggest guidelines for sediment mining. The study was carried out in the 1312 km long Narmada River basin, Central India using hydrological data (1987-2015), SRTM DEM and LULC data. We identified the major aggrading river reaches (100s of km long) on the basis of reach scale sediment mass balance analysis. These reaches are dominantly aggrading at the rate of ~50,000 tons/km/yr. Sediment yield values were used to identify major erosion hot spots in the river basin and its contribution to spatial variability in aggradation-degradation processes in the river channel. This spatial variability within channel was also ascertained through stream power and sediment supply relationship. Further, temporal variability in channel processes was observed in the aggrading reaches. This variability is mostly governed by sediment concentration. Higher sediment concentration (~1.5 g/l) in a given month may change degrading reaches into aggrading reaches. Spatial variability within aggrading reaches and sediment contribution from different sub-basins was further assessed through application of semi-distributed process based Soil and Water Assessment Tool (SWAT). SWAT-CUP yielded good calibration results (~ 40% of the measured data bracketed under the 95PPU envelope, for discharge and sediment load). SWAT was found to be suitable to analyze sediment yield distribution at HRU scale in the Narmada River basin, except for smaller and steeper subbasins where hillslope processes dominate. Further, spatial variability within these reaches was identified by analysis of bar dynamics. Satellite data based change detection analysis was used to identify aggrading channel bars. These bars may be focused for sand mining operations within the aggrading reaches, although limited to ~20% change in the sediment bar area.

We propose a new approach to unambiguous determination of parameters of positive and negative electric streamer discharges (streamers). We derive several relations between streamer parameters which allow us to express them in terms of the streamer length L and the external electric field E_e, as functions of streamer radius a. In particular, we find that the streamer velocity V(a) has a maximum at a certain value of radius a_s. We interpret the streamer as a nonlinear instability, whose behavior is determined by maximizing its growth rate, proportional to V. The radius of the streamer is therefore hypothesized to be equal to a_s, which fixes all streamer parameters. Thus, for the first time (to our knowledge) we prove that the streamer parameters are completely determined by E_e and L and suggest a simple way to calculate them that does not require hydrodynamic simulations. The parameters of streamers in air at sea level conditions, calculated in the proposed way, are compared and found to be compatible with experimental data [e.g., velocities obtained by Allen and Mikropoulos, 1999, doi:10.1088/0022-3727/32/8/012 and radii seen on the photographic images of Kochkin et al, 2016, doi:10.1088/0022-3727/49/42/425203], as well as with results of hydrodynamic simulations [Lehtinen and Østgaard, 2018, doi:10.1029/2018JD028646]. We also reproduce the correct values of streamer threshold fields of ~0.45 MV/m for positive streamers and ~0.75-1.25 MV/m for negative streamers.

An urban air temperature model is presented using GOES-16 land surface temperature. The Automated Surface Observing System (ASOS) serves as ground truth air temperature for calibration and testing of the model. The National Land Cover Database (NLCD) is used to calculate a weighted distribution of 20 land classifications for each satellite pixel surrounding a nearby ASOS station. A time-match algorithm aligns the ground and satellite measurements within 5-minutes of one another, and the resulting matched LST and air temperature are compared over nine months to investigate their cross-correlation. A model is constructed by fitting their difference using a gaussian profile. Landcover, latitude, longitude, local time, and elevation are inputted into an artificial regressive neural network to fit each unique GOES-16 pixel. Over 100 urban stations and satellite pixels throughout the continental U.S. are used to construct the diurnal gaussian model and approximate air temperature. Early statistics indicate favorable results, competing with other studies with more complicated and intensive calculations. The presentation of this model is intended to simplify the calculation of air temperature from satellite LST and create a successful model that performs well in urban environments. The improvement of urban air temperature calculations will also result in improved satellite land surface products such as relative humidity and heat index.

Analysis of topographic effects on global surface BRDF/Albedo Shengbiao Wu1,2 Jianguang Wen1,2 1Institute of Remote Sensing and Digital Earth, CAS, Beijing, 100101, China 2University of Chinese Academy of Sciences, Beijing, 100049, China Abstract: Rugged terrain significantly impacts surface reflectance anisotropy as it incurs variations in the illumination and viewing geometry, as well as the incoming irradiance. An accurate knowledge of such variation is crucial to improve the understanding land surface process and Earth’s surface radiation budget. To analyze the topographic effects on global-scale surface BRDF/Albedo, the 500 m moderate resolution imaging spectroradiometer (MODIS) daily global BRDF/Albedo Model Parameter (MCD43A1, collection 6) and MCD43A3 Albedo products, 30 m resolution Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation (ASTER GDEM, version 2), and 500 m MODIS Land Cover Type product (MCD12Q1, collection 6) from 2000-2016 were used. The topographic characteristic (e.g., slope, aspect, sky view factor) that extracted from ASTER GDEM datasets were used to statistic surface BRDF/Albedo of different land cover types under different topography conditions. The primarily results in Figure 1-3 show that surface BRF/Albedo is significantly decreased with the mean slope angles due to the increased topographic shadow. As the mean slope increases from 0° to 60°, the maximum value of grassland red (near-infrared: NIR) BRF decreases from 0.15 (0.35) to 0.10 (0.20), evergreen broadleaf red (NIR) BRF decrease from 0.04(0.45) to 0.03(0.40). Moreover, the grassland average shortwave black-sky (white-sky) albedo decreases from 0.17 (0.18) to 0.12 (0.14), and the evergreen broadleaf average shortwave black-sky (white-sky) albedo decreases from 0.13 (0.15) to 0.11 (0.13). Fig. 1. Topographic effects on grassland BRF of h26v05 and h26v06 on DOY 245, 2016. (a) 0°-10°. (b). 10°-20°. (c). 20°-30°. (d). 30°-40°. (e). 40°-50°. (f). ≥50° Fig. 2. Topographic effects on evergreen broadleaf forest BRF of h26v05 and h26v06 on DOY 245, 2016. (a) 0°-10°. (b). 10°-20°. (c). 20°-30°. (d). 30°-40°. (e). 40°-50°. (f). 50° Fig. 3. Topographic effects on black-sky and white-sky albedos of grassland and evergreen broadleaf forest of h26v05 and h26v06 on DOY 245, 2016

Over the past several decades, the Greenland Ice Sheet has been losing mass through a combination of increased surface runoff and accelerating ice flux to the ocean. Our understanding of the surface component is drawn heavily from satellite observations and climate models. The MAR (Modèle Atmosphère Régional) model is a 3D regional climate model used extensively over Greenland. Our study focuses on the surface snow and the ice down to 15-meter in depth. A light-weighted surface model for us to integrate the local observation data and force many simulations is needed. Our goal is to implement a surface-only model, derived from MAR, as a tool for understanding the glacial surface components, correlations, and MAR biases to improve projections of surface runoff. This model includes the ability to integrate observations from surface weather stations, translate the data into a model forcing format, force different simulations with various configurations or datasets, visualize model outputs, find key correlations between atmospheric drivers and modeled firn densification. In the model development, we extract the surface code from the original MAR for the simulations initialized and forced with the following snow and atmospheric fields: snow depth, temperature, density, water volume, and grain size. We then verify that the surface model generates the same outputs as the full MAR does if fetched with the identical data. The bias is checked with snowpack time-depth plots for multiple sites around Greenland, including Summit and Swiss Camp. We have found a very small bias when compared to the fully-coupled MAR. We perform quality control for the data inputs, such as replacing missing data from the station measurements, defining the max and min for each dataset, filtering out the data outliers by statistics standard deviations. As the result, our model software can provide multiple simulations in sequential and concurrent mode with user-friendly interfaces, and run robustly. The model’s first release is currently being deployed over different sites across Greenland to understand the importance of atmospheric forcing versus snow model biases in projections of future mass loss due to surface melt.