{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T15:38:57Z","timestamp":1773329937610,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,10,1]],"date-time":"2024-10-01T00:00:00Z","timestamp":1727740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100016811","name":"National Institute of Forest Science","doi-asserted-by":"publisher","award":["FM0103-2021-01-2024"],"award-info":[{"award-number":["FM0103-2021-01-2024"]}],"id":[{"id":"10.13039\/100016811","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This study aims to evaluate the representativeness of Calibration\/Validation (Cal\/Val) sites for satellite data, develop a framework for establishing new Cal\/Val sites, and propose a heterogeneity index to be applied within this framework, specifically focusing on South Korea. The proposed framework assesses the representativeness of existing Cal\/Val sites, and, if found inadequate, provides a methodology for optimizing the location and number of additional Cal\/Val sites, along with a prioritization strategy for their installation. Furthermore, the framework includes a methodology for evaluating the suitability of utilizing existing ground observation networks as additional Cal\/Val sites and for prioritizing their use. The heterogeneity index is derived by synthesizing differences in geographic, climatic, vegetation, and spectral characteristics between the current Cal\/Val sites and the broader regions. A higher heterogeneity index indicates significant divergence from existing Cal\/Val sites across these factors, highlighting areas with a need for additional Cal\/Val sites and a higher expected impact from their establishment. This index serves as a key tool within the framework to determine the optimal locations and number of new Cal\/Val sites, as well as to evaluate the efficacy of utilizing existing ground observation networks. The framework was applied to South Korea, where the representativeness of the current eight Cal\/Val sites was found to be insufficient. The optimal number of Cal\/Val sites was determined to be 33, requiring the addition of 25 new sites in South Korea. The southeastern peninsula and surrounding islands were identified as priority regions for new installations. Additionally, the potential for utilizing the existing ground observation network was examined. Twenty-three Automatic Mountain Meteorology Observation System (AMOS) sites in South Korea were selected and compared with the optimized Cal\/Val sites. The inclusion of these 23 AMOS sites was found to significantly improve representativeness, approaching the level of the optimized Cal\/Val sites. This strategic deployment is expected to enhance the accuracy and reliability of remote sensing data, contributing to improved environmental monitoring and research in South Korea.<\/jats:p>","DOI":"10.3390\/rs16193668","type":"journal-article","created":{"date-parts":[[2024,10,1]],"date-time":"2024-10-01T07:41:49Z","timestamp":1727768509000},"page":"3668","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Strategic Framework for Establishing Additional In Situ Data Acquisition Sites for Satellite Data Calibration and Validation: A Case Study in South Korean Forests"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1849-139X","authenticated-orcid":false,"given":"Cheolho","family":"Lee","sequence":"first","affiliation":[{"name":"National Forest Satellite Information & Technology Center, National Institute of Forest Science, Seoul 05203, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8413-6930","authenticated-orcid":false,"given":"Minji","family":"Seo","sequence":"additional","affiliation":[{"name":"National Forest Satellite Information & Technology Center, National Institute of Forest Science, Seoul 05203, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9026-5763","authenticated-orcid":false,"given":"Joongbin","family":"Lim","sequence":"additional","affiliation":[{"name":"National Forest Satellite Information & Technology Center, National Institute of Forest Science, Seoul 05203, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10689","DOI":"10.3390\/rs70810689","article-title":"Estimating the influence of spectral and radiometric calibration uncertainties on EnMAP data products\u2014Examples for ground reflectance retrieval and vegetation indices","volume":"7","author":"Bachmann","year":"2015","journal-title":"Remote Sens."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e2022JD036779","DOI":"10.1029\/2022JD036779","article-title":"Characterizing the Effect of Spatial Heterogeneity and the Deployment of Sampled Plots on the Uncertainty of Ground \u201cTruth\u201d on a Coarse Grid Scale: Case Study for Near-Infrared (NIR) Surface Reflectance","volume":"127","author":"Wen","year":"2022","journal-title":"J. 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