ESSDD Earth System Science Data Discussions ESSDD Earth Syst. Sci. Data Discuss. 1866-3591 Göttingen, Germany 10.5194/essd-2024-615 The JapanFlux2024 dataset for eddy covariance observations covering Japan and East Asia from 1990 to 2023 Ueyama Masahito https://orcid.org/0000-0002-4000-4888 1 Takao Yuta 1 Yazawa Hiromi 2 Tanaka Makiko 2 Yabuki Hironori 3 Kumagai Tomo’omi 4 Iwata Hiroki 5 Awal Md. Abdul 6 Du Mingyuan 7 Harazono Yoshinobu 8 Hata Yoshiaki https://orcid.org/0000-0001-7703-0863 4 Hirano Takashi 9 Hiura Tsutom 4 Ide Reiko 10 Ishida Sachinobu https://orcid.org/0000-0001-9934-2980 11 Ishikawa Mamoru 12 Kitamura Kenzo 13 Kominami Yuji 14 Komiya Shujiro https://orcid.org/0000-0001-6185-4366 15 Kotani Ayumi https://orcid.org/0000-0003-0350-0775 16 Inoue Yuta 14 Machimura Takashi https://orcid.org/0000-0001-9978-8843 17 Matsumoto Kazuho 18 Matsuura Yojiro 14 Mizoguchi Yasuko 19 Murayama Shohei 20 Nagano Hirohiko https://orcid.org/0000-0002-3090-7709 21 Nakai Taro https://orcid.org/0000-0002-6107-0614 22 Nakaji Tatsuro 23 Nakaya Ko 24 Ohkubo Shinjiro https://orcid.org/0000-0002-3644-9585 25 Ohta Takeshi 26 Ono Keisuke 27 Saitoh Taku M. 28 Sakabe Ayaka 29 Shimizu Takanori 14 Shimoda Seiji 30 Sugita Michiaki https://orcid.org/0000-0002-2241-9334 31 Takagi Kentaro https://orcid.org/0000-0002-1321-2841 32 Takahashi Yoshiyuki 10 Takamura Naoya 4 Takanashi Satoru 33 Takimoto Takahiro 27 Yasuda Yukio 14 Wang Qinxue https://orcid.org/0000-0001-7723-5412 10 Asanuma Jun https://orcid.org/0000-0003-1258-5491 34 Hasegawa Hideo 21 Hiyama Tetsuya 35 Iijima Yoshihiro 36 Ishidoya Shigeyuki https://orcid.org/0000-0001-7448-2899 20 Itoh Masayuki 37 Kato Tomomichi https://orcid.org/0000-0003-3757-3243 9 Kondo Hiroaki 20 Kosugi Yoshiko 29 Kume Tomonori 38 Maeda Takahisa 20 Maximov Trofim 39 Moriwaki Ryo 40 Muraoka Hiroyuki 28 Petrov Roman 39 Suzuki Jun 41 Taniguchi Shingo 42 Ichii Kazuhito 2 Graduate School of Agriculture, Osaka Metropolitan University, Sakai 599-8531, Japan Center for Environmental Remote Sensing (CEReS), Chiba University, Chiba 263-8522, Japan National Institute of Polar Research (NIPR), Tokyo 190-8518, Japan Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan Department of Environmental Science, Faculty of Science, Shinshu University, Matsumoto 390-8621, Japan Department of Crop Botany, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh Xingjiang Institute of Ecology and Geography, Chinese Academy Of Sciences, Xinjiang 830011,China International Arctic Research Center, University of Alaska Fairbanks, Fairbanks, AK 99775, USA Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan National Institute for Environmental Studies, Tsukuba 305-8506, Japan Graduate School of Science and Technology, Hirosaki University, Hirosaki 036‑8561, Japan Faculty of Earth Environmental Science, Hokkaido University, Sapporo 060-0810 Japan Kyushu Research Center, Forestry and Forest Products Research Institute, Kumamoto 860-0862, Japan Forestry and Forest Products Research Institute, Tsukuba 305-8687, Japan Department of Biogeochemical Processes, Max Planck Institute for Biogeochemistry, Jena 07745, Germany Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan Graduate School of Engineering, Osaka University, Suita 565-0871, Japan Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan Hokkaido Research Center, Forestry and Forest Products Research Institute, Sapporo 062-8516, Japan National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8569, Japan Institute of Science and Technology, Niigata University, Niigata 950-2181, Japan School of Forestry and Resource Conservation, National Taiwan University, Taipei 106319, Taiwan Sapporo Experimental Forest, Hokkaido University, Sapporo 060-0809, Japan Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry, Abiko 270-1194, Japan Forestry Research Institute, Forest Research Department, Hokkaido Research Organization, Bibai 079-0198, Japan Professor emeritus, Nagoya University, Nagoya 464-8601 Japan Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba 305-8604 Japan Center for Environmental and Societal Sustainability, Gifu University, Gifu 501-1193, Japan Graduate School of Agriculture, Kyoto University, Kyoto 606-8501 Japan Memuro Research Station, Hokkaido Agricultural Research Center, NARO, (HARC/M /NARO), Memuro 082-0081, Japan Institute of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan Field Science Center for Northern Biosphere, Hokkaido University, Toikanbetsu, 098-2943, Japan Kansai Research Center, Forestry and Forest Products Research Institute, Kyoto 612-0855, Japan Center for Research in Isotopes and Environmental Dynamics (CRiED), University of Tsukuba, Tsukuba 305-8572, Japan Institute for Space-Earth Environmental Research, Nagoya University, Nagoya 464-8601, Japan Department of Geography, Tokyo Metropolitan University, Tokyo 192-0397 Japan Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan Kasuya Research Forest, Kyushu University, Fukuoka 811-2415, Japan Institute for Biological Problems of Cryolithozone, Yakutsk 677980, Russia Faculty of Engineering, Ehime University, Matsuyama 790-8577, Japan Faculty of Agriculture, Shinshu University, Nagano 399-4598, Japan Faculty of Agriculture, University of the Ryukyus, Okinawa 903-0213, Japan 12 02 2025 2025 1 47 Copyright: © 2025 Masahito Ueyama et al. 2025 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/ This article is available from https://essd.copernicus.org/preprints/essd-2024-615/ The full text article is available as a PDF file from https://essd.copernicus.org/preprints/essd-2024-615/essd-2024-615.pdf

Eddy covariance observations play a pivotal role in understanding the land&ndash;atmosphere exchange of energy, water, carbon dioxide (CO<sub>2</sub>), and other trace gases, as well as the global carbon cycle and earth system. To promote the networking of individual measurements and the sharing of data, FLUXNET links regional networks of researchers studying land&ndash;atmosphere processes. JapanFlux was established in 2006 as a country branch of AsiaFlux. Despite the growing number of shared data globally, the availability in Asia is currently limited. In this study, we developed an open dataset of the eddy covariance observations for Japan and East Asia, called JapanFlux2024, that was conducted by researchers affiliated with Japanese research institutions. The dataset consists of data collected at 79 sites with 652 site-years from 1990 to 2023. The data format is fully compatible with the recent FLUXNET data product, FLUXNET2015. Here, we present the data description and data processing and show the value of processed fluxes of sensible heat, latent heat, and CO<sub>2</sub>. The dataset will facilitate important studies for Japan and East Asia, such as land-atmosphere interactions, improvement of process models, and upscaling fluxes using machine learning and remote sensing technology as well as bridge collaborations between Asia and FLUXNET.

 Japan Society for the Promotion of Science 21H05316 19H05668 JPJSA3F20220002 2331001513 2529207903 18H03362 24K03065 25450201 22H05711 22H05004 24H01504 17H05039 21H02315 23K21248 23KK0194 15K01159 20H01384 23K20125 20H0309 21H05312 19H03301 18780113 21241009 22248017 23710005 24241008 26241005 26292092 15H04512 20H03041 20K06144 21H02245 23K11395 24K01818 24K00986 24310017 15H02814 18H03365 19H01975 22H00564 22H05006 11213204 14656059 16208014 19H03077 19H03085 23H02341 25304027 16H02762 21H02238 22K05752 24H01520 Ministry of Education, Culture, Sports, Science and Technology JPMXD1420318865 Ministry of the Environment, Government of Japan JPMEERF24S12207 MAFF0751 MAFF1251 MAFF2254 199903 200303 Environmental Restoration and Conservation Agency JPMEERF20232M01