DOI: 10.5061/dryad.2z34tmpwj
title: Selected large model output files and Buffalo sounding data from: Lake Huron enhances snowfall downwind of Lake Erie: a modeling study of the 2010 near year’s Lake-effect snowfall event

description: In the Northeast and Great Lakes regions of the United States, the
 influence of multiple lakes on overlying air can greatly affect
 lake-effect snowfall over downwind communities. To assess the impact of
 Lake Huron on snowfall downwind of Lake Erie, we simulated a lake-effect
 snow event which occurred from 1-6 January 2010 using the Regional
 Atmospheric Modeling System (RAMS). We found that the presence of Lake
 Huron enhances snowfall downwind of Lake Erie by almost 20\% and leads to
 much heavier local snowfall totals than when Lake Huron is not present.
 This increase in snowfall is due to a lake-to-lake (L2L) convective band,
 as secondary circulations associated with lake-effect convection form over
 Lake Huron and persist overland between the lakes before re-intensifying
 over Lake Erie. As these secondary circulations move over Lake Erie,
 low-level convergence from the secondary circulation induces mechanical
 lifting which accelerates the development of convection within the L2L
 band. Surface fluxes and convection over Lake Huron deepen the boundary
 layer, promoting deeper vertical development of this L2L band over Lake
 Erie. However, although this boundary layer modification strengthens the
 L2L band, we found that it actually reduced lake-effect snowfall produced
 by wind-parallel bands (WPB) in other parts of the lake. This indicates
 that boundary layer modification from upstream lakes may impact L2L bands
 differently than WPB which are not connected to upstream secondary
 circulations.
description: This dataset was produced by simulating a lake-effect snow event
 which occurred between 1-3 January 2010 with the Regional Atmospheric
 Modeling System (RAMS), an open-source, nonhydrostatic numerical weather
 model. The model was initiatlized and forced at lateral boundaries with
 ERA5 reanalysis data. Three simulations were conducted: A CONTROL
 simulation, without any modifications to the reanalysis, and which used
 initial water temperatures from a 1-degree horizontal resolution
 Reynolds-averaged global dataset, a NLH simulation in which the surface of
 Lake Huron was changed from water to mixed forest and in which initial
 soil and snow data over the former area of Lake Huron were adjusted to
 match those of neighboring Michigan, and a VARTEMP simulation which was
 identical to CONTROL except that data from the Great Lakes Environmental
 Research Laboratory (GLERL) were used for the initial water temperatures
 over the Great Lakes. The model output files use a
 terrain-following sigma-z vertical grid structure and an Arakawa C-grid
 structure for vector quantities. To simplify analysis, we developed a
 post-processing routine for RAMS data to convert this grid structure to a
 standard Cartesian grid. We also output several derived variables in this
 post-processed output. A PDF file describing the
 variables included in the RAMS analysis output files (those with extension
 .h5) as well as a .txt. file describing the variables present within the
 post-processed files (those with extension .nc) have also been uploaded
 here. Finally, we have included the Buffalo sounding
 data used to construct Figure 4. This data comes from the National Oceanic
 and Atmospheric Administration (NOAA) Integrated Global Radiosonde Archive
 and is provided in .txt form. A product description PDF, as well as a
 README .txt file taken from NOAA which describes the structure,
 organization, and units within the bufsoundings_por.txt file, have also
 been uploaded here. We should note that this collection
 is not intended for full data reproduction, but rather for those who would
 like to examine the raw and post-processed model data at a particular time
 of interest, in this case 2300 UTC on 2 January 2010. This is the time at
 which the bulk of the analysis and figures within the manuscript are
 focused, and therefore these data should allow for the reproduction of
 figures 7-8 and 10-14 as seen within the manuscript. For a guide to full
 data reproduction, please see the Zenodo repository at the following DOI:
 https://doi.org/10.5281/zenodo.10889801.
 <pre> </pre>
description: # Selected large model output files and Buffalo sounding data from: Lake
 Huron enhances snowfall downwind of Lake Erie: a modeling study of the
 2010 near year’s Lake-effect snowfall event
 [https://doi.org/10.5061/dryad.2z34tmpwj](https://doi.org/10.5061/dryad.2z34tmpwj) ## Description of the data and file structure This data was collected for the paper entitled "Lake Huron Enhances Snowfall Downwind of Lake Erie: A Modeling Study of the 2010 New Year's Lake-Effect Snowfall Event." With the exception of the file containing radiosonde data from Buffalo Niagara International Airport, which was obtained from the Integrated Global Radiosonde Archive from the National Oceanic and Atmospheric Administration (NOAA), all other files are either raw or post-processed output from the Regional Atmospheric Modeling System (RAMS) simulations of the lake-effect snow event which occurred over the North American Great Lakes from 1-3 January 2010. This data is not meant to replace the repository for full data and figure reproduction here: [https://doi.org/10.5281/zenodo.14212949](https://doi.org/10.5281/zenodo.14212949), but rather to provide a subset of post-processed and raw output files from 2300 UTC on 2 January, the time of most plan views in the paper, as well as post-processed files from 0000 UTC on 3 January, which can be compared with sounding data from Buffalo at this time. ### Files and variables #### File: Large\_Files.zip **Description:** Within the main "Large Files" folder, there are three subfolders: hires_control, hires_nolake, and hires_vartemp, as well as a file called bufsoundings_por. hires_control contains post-processed and raw output file data for the CONTROL simulation at 2300 UTC on 2 January, as well as post-processed data for 0000 UTC on 3 January. hires_nolake contains post-processed and raw output file data for the NLH simulation at 2300 UTC on 2 January, while hires_vartemp contains raw output file data for the VARTEMP simulation at 2300 UTC on 2 January. bufsoundings_por contains radiosonde data collected from the Buffalo Niagara International Airport from NOAA's Integrated Global Radiosonde Archive. Radiosonde data from 0000 UTC on 3 January can be compared with CONTROL post-processed data from the same time and latitude/longitude. The post-processed data is stored in the .nc format, while the raw model data is stored in the .h5 format. The bufsoundings_por file is .txt. #### File: igra2-data-format.txt (on Zenodo as Supp Info) **Description:** This file describes the structure, fields, and units of the data present in the bufsoundings_por.txt file. This file was accessed from the following url: [https://www.ncei.noaa.gov/data/integrated-global-radiosonde-archive/doc/igra2-data-format.txt](https://www.ncei.noaa.gov/data/integrated-global-radiosonde-archive/doc/igra2-data-format.txt) #### File: igra2-product-description.pdf (on Zenodo as Supp Info) **Description:** This file describes the data sourcing and quality control for the radiosonde data present in the bufsoundings_por.txt file. This file was accessed from the following url: [https://www.ncei.noaa.gov/data/integrated-global-radiosonde-archive/doc//igra2-product-description.pdf](https://www.ncei.noaa.gov/data/integrated-global-radiosonde-archive/doc//igra2-product-description.pdf) #### File: RAMS-VariableList.pdf (on Zenodo as Supp Info) **Description:** This file lists the variables which are present in the RAMS analysis output files (those with .h5 extensions) and gives descriptions of their dimensions, units, and physical interpretation. This file was accessed from the following url: [https://github.com/RAMSmodel/RAMS/blob/main/docs/RAMS-VariableList.pdf](https://github.com/RAMSmodel/RAMS/blob/main/docs/RAMS-VariableList.pdf) #### File: postprocessvars-list.pdf (on Zenodo as Supp Info) **Description:** This file provides a brief overview of the RAMS post-processed files (those with .nc extensions) and gives a list of variables present within these files, along with their dimensions and units. ## Code/software Python 3.8 or higher, together with packages jupyter, numpy, metpy, xarray, and matplotlib, is recommended to examine the .h5, .nc, and .txt files within this dataset. ## Access information Data was derived from the following sources: * Radiosonde data was obtained from the Integrated Global Radiosonde Archive organized by the National Oceanic and Atmospheric Administration (NOAA), and is available here: [https://www.ncei.noaa.gov/products/weather-balloon/integrated-global-radiosonde-archive](https://www.ncei.noaa.gov/products/weather-balloon/integrated-global-radiosonde-archive) * Model output data was generated with the Regional Atmospheric Modeling System (RAMS), available here: [https://github.com/RAMSmodel/RAMS](https://github.com/RAMSmodel/RAMS) * Model post-processed data was generated with the rams-postprocess python toolkit, available here: [https://github.com/benaplus1/rams_postprocess](https://github.com/benaplus1/rams_postprocess)