Link echolevels in docs

docs/source/processing-levels.md

@@ -1,63 +1,7 @@
-# Proposed Echosounder Data Processing Levels (DRAFT)
+# Echosounder data processing levels
 
-The decades-long experience from the satellite remote sensing community has shown that a set of robust and well-articulated definitions of "data processing levels" [1]–[5] can lead directly to broad and highly productive use of data. Processing level designations also provide important context for data interpretation [6]. However, no such community agreement exists for active acoustic data. The ambiguity associated with the interoperability and inter-comparability of processed sonar data products has hindered efficient collaboration and integrative use of the rapidly growing data archive across research institutions and agencies.
+The decades-long experience from the satellite remote sensing community has shown that a set of robust and well-articulated definitions of "data processing levels" {cite}`weaver_2014` can lead directly to broad and highly productive use of data. Processing level designations also provide important context for data interpretation {cite}`hills_2015`. However, no such community agreement exists for echosounder data. Improving the interoperability and inter-comparability of processed echosounder data products will likely facilitate efficient collaboration and integrative use of the rapidly growing data archive across research institutions and agencies.
 
-The `echopype` team is developing a clearly defined progression of data processing levels for active ocean sonar data. The development leverages the collective experience from remote sensing and large-scale, long-term ocean and ecological observatories [7]–[10]. Data processing functions in `echopype` are clearly associated with specific Processing Level inputs and outputs, and when appropriate, will generate a `processing_level` dataset global attribute with entries such as "Level 1A", "Level 2B", "Level 4", etc.
+To help address this gap, the echopype team is developing a clearly defined progression of echosounder data, by leveraging the collective experience from remote sensing and large-scale, long-term ocean and ecological observatories.
 
-
-## Processing Levels and Sub-levels
-
-### Level 0 (L0)
-
-**Description:**  Raw data in vendor sensor format.
-
-- raw binary files. Associated metadata may be found in external files.
-
-### Level 1 (L1)
-
-**Description:** Raw data packaged with ancillary information and converted and standardized to an open convention and standard data formats. May be distributed in the following two forms:
-  - as sets of individual converted files as originally segmented into arbitrary time ranges during sensor file creation, or
-  - compiled into larger granules corresponding to logical deployment intervals.
-
-- **L1A**: Raw L0 data converted to a standardized, open format with geographic coordinates (latitude & longitude) included. Includes other ancillary information extracted from sensor-generated L0 data or other external sources. May include environmental information such as temperature, salinity and pressure. Use of the SONAR-netcDF4 version 1 convention is strongly recommended.
-- **L1B**: L1A data with quality-control steps applied, such as time-coordinate corrections that enforce strictly increasing, non-duplicate timestamps.
-
-### Level 2 (L2)
-
-**Description:** Calibrated acoustic quantities at raw data resolution, with spatial coordinates included (latitude, longitude and depth)
-
-- **L2A**: Volume backscattering strength (`Sv`) with interpolated latitude, longitude and depth coordinates. May incorporate addition information, such as  split beam angle
-- **L2B**: `Sv` L2A data with noise removal or other data filtering applied, including seafloor bottom removal.
-
-### Level 3 (L3)
-
-**Description:** Calibrated acoustic quantities regridded or aggregated to a common grid across channels. May include noise removal or other filtering.
-
-- `Sv` resampled to a common, high-resolution grid across channels
-- Mean Volume Backscattering Strength (`MVBS`)
-- Masks applied to `Sv` based on different scattering source classification criteria and methods, such as frequency difference across two channels.
-- **L3A**: The above variables computed on L2A data
-- **L3B**: The above variables computed on L2B (filtered) data
-
-### Level 4 (L4)
-
-**Description:** Acoustically derived biological features, involving further processing of L3 data that may include data reduction or incorporation of external sources of data.
-
-- Nautical Area Backscattering Coefficients (`NASC`), potentially partitioned into inferred sources of scattering
-- Summary statistics of echogram features (center_of_mass, dispersion, etc)
-- Taxon or species-level data labels (classification). May originate from a variety of methods, including frequency difference thresholds.
-- Estimated biomass, combined or partitioned into different taxonomic sources.
-
-
-## References
-
-- [1] Parkinson, C. L., A. Ward, and M. D. King (eds.). 2006. Earth science reference handbook: A guide to NASA’s Earth Science Program and Earth Observing Satellite Missions. National Aeronautics and Space Administration. https://atrain.nasa.gov/publications/2006ReferenceHandbook.pdf
-- [2] NASA. 2021. Data Processing Levels | Earthdata. Last viewed Mar. 24, 2023. https://earthdata.nasa.gov/collaborate/open-data-services-and-software/data-information-policy/data-levels/
-- [3] Ramapriyan, H. K., and P. J. T. Leonard. 2021. Data Product Development Guide (DPDG) for Data Producers version1.1. NASA Earth Science Data and Information System Standards Office, 21 October 2021. https://doi.org/10.5067/DOC/ESO/RFC-041VERSION1
-- [4] Robinson, I. 2006. Satellite Measurements for Operational Ocean Models, pp. 147-189. In: Chassignet, E.P. and Verron, J. (eds). Ocean Weather Forecasting: An Integrated View of Oceanography. Springer, New York, NY. https://doi.org/10.1007/1-4020-4028-8_6
-- [5] Weaver, R. 2014. Processing Levels, pp. 517-520. In: Njoku, E.G. (ed). Encyclopedia of Remote  Sensing. Encyclopedia of Earth Sciences Series. Springer, New York, NY.  https://doi.org/10.1007/978-0-387-36699-9_36
-- [6] Hills, D. J., R. R. Downs, R. Duerr, J. C. Goldstein, M. A. Parsons, and H. K. Ramapriyan. 2015. The importance of data set provenance for science. Eos, 96, Published on 4 December 2015. https://doi.org/10.1029/2015EO040557
-- [7] Heaney, K., B. Martin, J. Miksis-Olds, T. Moore, J. Warren, and M. Ainslie. 2020. ADEON data processing specification. Version 1.0. Technical report by Applied Ocean Sciences for Prime Contract No. M16PC00003, Apr. 2020. https://adeon.unh.edu/sites/default/files/user-uploads/ADEON_Data%20Processing_Specification_FINAL.pdf
-- [8] IFREMER. 2019. Processing Levels - Oceanographic Data. Last viewed Mar. 24, 2023. http://en.data.ifremer.fr/All-about-data/Data-management/Processing-levels
-- [9] NEON. 2023 Data Processing | NSF NEON | Open Data to Understand our Ecosystems. Last viewed Mar. 24, 2023. https://www.neonscience.org/data-samples/data-management/data-processing
-- [10] OOI. 2023. Ocean Observatories Initiative: Glossary - Data Terminology. Ocean Observatories Initiative. Last viewed Mar. 24, 2023. https://oceanobservatories.org/glossary/#DATATERMS
+See the [echolevels](http://echolevels.readthedocs.io/) document for the current status, and please chime in with any [input or questions via GitHub issues](https://github.com/uw-echospace/data-processing-levels/issues/new).

docs/source/references.bib

@@ -8,6 +8,7 @@ @article{DeRobertis2007_noise
 	year = {2007},
 	pages = {1282--1291},
 }
+
 @techreport{Demer2015,
 	title = {Calibration of acoustic instruments},
 	institution = {ICES Cooperative Research Report, No. 326},
@@ -16,6 +17,7 @@ @techreport{Demer2015
 	doi = {10.17895/ices.pub.5494},
 	pages = {133 pp},
 }
+
 @article{MacKenzie1981,
 	title = {Nine-term equation for sound speed in the oceans},
 	volume = {70},
@@ -26,6 +28,7 @@ @article{MacKenzie1981
 	pages = {807--812},
 	doi = {10.1121/1.386920},
 }
+
 @article{Ainslie1998,
 	title = {A simplified formula for viscous and chemical absorption in sea water},
 	volume = {103},
@@ -39,3 +42,31 @@ @article{Ainslie1998
 	note = {Publisher: Acoustical Society of America},
 	pages = {1671--1672},
 }
+
+@incollection{weaver_2014,
+	address = {New York, NY},
+	series = {Encyclopedia of {Earth} {Sciences} {Series}},
+	title = {Processing {Levels}},
+	isbn = {978-0-387-36699-9},
+	language = {en},
+	booktitle = {Encyclopedia of {Remote} {Sensing}},
+	publisher = {Springer},
+	author = {Weaver, Ron},
+	editor = {Njoku, Eni G.},
+	year = {2014},
+	doi = {10.1007/978-0-387-36699-9_36},
+	pages = {517--520},
+	file = {Full Text PDF:/Users/wujung/Zotero/storage/K8CUALCF/Weaver - 2014 - Processing Levels.pdf:application/pdf},
+}
+
+@misc{hills_2015,
+	title = {The {Importance} of {Data} {Set} {Provenance} for {Science}},
+	url = {http://eos.org/opinions/the-importance-of-data-set-provenance-for-science},
+	abstract = {Data do not exist in a vacuum. To be useful, data must be accompanied by context on how they are captured, processed, analyzed, and validated and other information that enables interpretation and use.},
+	language = {en-US},
+	urldate = {2023-10-23},
+	journal = {Eos},
+	author = {Hills, D. J. and Downs, R. R. and Duerr, R. and Goldstein, J. C. and Parsons, M. A. and Ramapriyan, H. K.},
+	month = dec,
+	year = {2015},
+}