fix missing chen @

paper.md

@@ -37,11 +37,11 @@ River and Basin Profiler (`rabpro`) is a Python package to delineate watersheds,
 
 ## Statement of Need
 
-Watersheds play a central and vital role in many scientific, engineering, and environmental management applications (See @brooks_hydrology_2003 for a comprehensive overview). While `rabpro` can benefit any watershed-based research or analysis, it was designed to satisfy the needs of data-driven rainfall-runoff models. These models aim to predict streamflow (runoff) time series as a function of precipitation over upstream land area (i.e. the watershed). In addition to watershed delineations and precipitation estimates, they typically require data on both time-varying parameters (or forcing data) like temperature, humidity, soil moisture, and vegetation as well as static watershed properties like topography, soil type, or land use/land cover [@kratzert_toward_2019; @gauch_rainfallrunoff_2021; @nearing_data_2021; @kratzert_note_2021]. The `rabpro` API enables users to manage the complete data pipeline necessary to drive such a model starting from the initial watershed delineation through the calculation of static and time-varying parameters. Some hydrologic and hydraulic models also require channel slope for routing streamflow [@boyle_toward_2001; @piccolroaz_hyperstream_2016; @wilson_water_2008], developing rating curves [@fenton_calculation_2001; @colby_relationship_1956], or modeling local hydraulics [@schwenk_life_2015; @schwenk_high_2017; @schwenk_meander_2016]. 
+Watersheds play a central and vital role in many scientific, engineering, and environmental management applications (See @brooks_hydrology_2003 for a comprehensive overview). While `rabpro` can benefit any watershed-based research or analysis, it was designed to satisfy the needs of data-driven rainfall-runoff models. These models aim to predict streamflow (runoff) time series as a function of precipitation over upstream land area (i.e. the watershed). In addition to watershed delineations and precipitation estimates, they typically require data on both time-varying parameters (or forcing data) like temperature, humidity, soil moisture, and vegetation as well as static watershed properties like topography, soil type, or land use/land cover [@kratzert_toward_2019; @gauch_rainfallrunoff_2021; @nearing_data_2021; @kratzert_note_2021]. The `rabpro` API enables users to manage the complete data pipeline necessary to drive such a model starting from the initial watershed delineation through the calculation of static and time-varying parameters. Some hydrologic and hydraulic models also require channel slope for routing streamflow [@boyle_toward_2001; @piccolroaz_hyperstream_2016; @wilson_water_2008], developing rating curves [@fenton_calculation_2001; @colby_relationship_1956], or modeling local hydraulics [@schwenk_life_2015; @schwenk_high_2017; @schwenk_meander_2016].
 
 The need for watershed-based data analysis tools is exemplified by the growing collection of published datasets that provide watershed boundaries, forcing data, and/or watershed attributes in precomputed form, including CAMELS [@addor_camels_2017], CAMELS-CL, -AUS, and -BR [@alvarez-garreton_camels-cl_2018; @fowler_camels-aus_2021; @chagas_camels-br_2020], Hysets [@arsenault_comprehensive_2020], and HydroAtlas [@linke_global_2019]. These datasets provide off-the-shelf options for building streamflow models, but they suffer from a degree of inflexibility. For example, someone desiring to add a watershed attribute, to use a new remotely-sensed data product, or to update the forcing data time-series to include the most recently available data must go through the arduous process of sampling it themselves. `rabpro` was designed to provide flexibility for both building a watershed dataset from scratch or appending to an existing one.
 
-While we point to streamflow modeling as an example, many other applications exist. `rabpro` is currently being used to contextualize streamflow trends, build a data-driven model of riverbank erosion, and generate forcing data for a mosquito population dynamics model. `rabpro`'s focus is primarily on watersheds, but some users may also find `rabpro`'s Google Earth Engine wrapper convenient for sampling raster data over any geopolygon(s).  For example, Earth System Models commonly require sampling raster datasets over watersheds or other polygons for parameterizations and validations [@fisher2019parametric; chen2020global].
+While we point to streamflow modeling as an example, many other applications exist. `rabpro` is currently being used to contextualize streamflow trends, build a data-driven model of riverbank erosion, and generate forcing data for a mosquito population dynamics model. `rabpro`'s focus is primarily on watersheds, but some users may also find `rabpro`'s Google Earth Engine wrapper convenient for sampling raster data over any geopolygon(s).  For example, Earth System Models commonly require sampling raster datasets over watersheds or other polygons for parameterizations and validations [@fisher2019parametric; @chen2020global].
 
 ## State of the field
 
@@ -53,7 +53,7 @@ One unique `rabpro` innovation is its automation of “hydrologically addressing
 
 ## Functionality
 
-`rabpro` executes watershed delineation based on either the MERIT-Hydro dataset, which provides a global, ~90 meter per pixel, hydrologically-processed DEM suite, or the HydroBASINS data product, which provides pre-delineated subbasins at approximately ~230 km^2 per subbasin. Conceptually, basin delineation is identical for both. The user-provided coordinate is hydrologically addressed by finding the downstream-most pixel (MERIT-Hydro) or subbasin (HydroBASINS). The watershed is then delineated by finding all upstream pixels or subbasins that drain into the downstream pixel/subbasin and taking the union of these pixels/subbasins to form a single polygon. A user must therefore download either the MERIT-Hydro tiles covering their study watershed or the appropriate HydroBASINS product; `rabpro` provides tooling to automate these downloads and create its expected data structure (See the Downloading data [notebook](https://github.com/VeinsOfTheEarth/rabpro/blob/main/docs/source/examples/notebooks/downloading_data.ipynb)). `rabpro` does not currently provide support for custom watershed datasets similar to HydroBASINS due to attribute field and data structure requirements that must be consistent for generalizability. 
+`rabpro` executes watershed delineation based on either the MERIT-Hydro dataset, which provides a global, ~90 meter per pixel, hydrologically-processed DEM suite, or the HydroBASINS data product, which provides pre-delineated subbasins at approximately ~230 km^2 per subbasin. Conceptually, basin delineation is identical for both. The user-provided coordinate is hydrologically addressed by finding the downstream-most pixel (MERIT-Hydro) or subbasin (HydroBASINS). The watershed is then delineated by finding all upstream pixels or subbasins that drain into the downstream pixel/subbasin and taking the union of these pixels/subbasins to form a single polygon. A user must therefore download either the MERIT-Hydro tiles covering their study watershed or the appropriate HydroBASINS product; `rabpro` provides tooling to automate these downloads and create its expected data structure (See the Downloading data [notebook](https://github.com/VeinsOfTheEarth/rabpro/blob/main/docs/source/examples/notebooks/downloading_data.ipynb)). `rabpro` does not currently provide support for custom watershed datasets similar to HydroBASINS due to attribute field and data structure requirements that must be consistent for generalizability.
 
 There are three primary operations supported by `rabpro`: 1) basin delineation, 2) elevation profiling, and 3) subbasin (zonal) statistics. If operating on a single coordinate pair, the cleanest workflow is to instantiate an object of the `profiler` class and call (in order) the `delineate_basins()`, `elev_profile()`, and `basin_stats()` methods (See the [Basic Example](https://veinsoftheearth.github.io/rabpro/examples/notebooks/basic_example.html) notebook). If operating on multiple coordinate pairs, the workflow is to loop through each coordinate pair while delineating each watershed (optionally calculating its elevation profile). As the loop runs, the user collects each basin polygon in a list, concatenates the list, and directly calls  `basin_stats.compute()` on the resulting GeoDataFrame (See the [Multiple Basins Example](https://veinsoftheearth.github.io/rabpro/examples/notebooks/multiple_basins.html) notebook). More details on package functionality can be found in [the documentation](https://VeinsOfTheEarth.github.io/rabpro/).