Abstract: Global Change BiologyVolume 28, Issue 23 p. 7157-7158 CORRIGENDUMFree Access Corrigendum This article corrects the following: ForestTemp – Sub-canopy microclimate temperatures of European forests Stef Haesen, Jonas J. Lembrechts, Pieter De Frenne, Jonathan Lenoir, Juha Aalto, Michael B. Ashcroft, Martin Kopecký, Miska Luoto, Ilya Maclean, Ivan Nijs, Pekka Niittynen, Johan Hoogen, Nicola Arriga, Josef Brůna, Nina Buchmann, Marek Čiliak, Alessio Collalti, Emiel De Lombaerde, Patrice Descombes, Mana Gharun, Ignacio Goded, Sanne Govaert, Caroline Greiser, Achim Grelle, Carsten Gruening, Lucia Hederová, Kristoffer Hylander, Jürgen Kreyling, Bart Kruijt, Martin Macek, František Máliš, Matěj Man, Giovanni Manca, Radim Matula, Camille Meeussen, Sonia Merinero, Stefano Minerbi, Leonardo Montagnani, Lena Muffler, Romà Ogaya, Josep Penuelas, Roman Plichta, Miguel Portillo-Estrada, Jonas Schmeddes, Ankit Shekhar, Fabien Spicher, Mariana Ujházyová, Pieter Vangansbeke, Robert Weigel, Jan Wild, Florian Zellweger, Koenraad Van Meerbeek, Volume 27Issue 23Global Change Biology pages: 6307-6319 First Published online: October 3, 2021 First published: 30 September 2022 https://doi.org/10.1111/gcb.16440AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat In the paper by Haesen et al. (2021), a coding mistake was found in the calculation of the monthly mean temperature offset values, which were used as the response variable in the model. Particularly, when calculating the monthly mean temperatures of each of the in situ temperature time series, these time series were shifted half a month forward leading to a temporal mismatch with the macroclimate data. This coding mistake led to a systematic overestimation in the magnitude of the offset values. However, the main message of this article still upholds after correcting for this systematic overestimation: (i) forest microclimates are overall warmer than the macroclimate during winter and overall colder than the macroclimate during summer; (ii) the high-resolution maps expose considerable microclimatic variation within landscapes, not captured by the gridded macroclimatic products; and (iii) these novel maps will fundamentally change the trustworthiness of ecological models in a range of disciplines, from biogeography over community ecology to ecosystem functioning. Finally, the corrected grid layers have been updated on figshare (https://doi.org/10.6084/m9.figshare.14618235). The full corrected version of the article, with all corrected figures (Figures 1–5), can be found within the supplementary materials to this corrigendum. What follows below, ordered according to the different sections of the article, is an overview of the most important changes and corrections made in the main text. Abstract Original text: “We found that sub-canopy air temperatures differ substantially from free-air temperatures, being on average 2.1°C (standard deviation ±1.6°C) lower in summer and 2.0°C higher (± 0.7°C) in winter across Europe.” This statement above should read as below given that the coding mistake led to a systematic overestimation in the magnitude of the offset values: Corrected text: “We found that sub-canopy air temperatures differ substantially from free-air temperatures, being on average 0.6°C (standard deviation ±0.8°C) lower in summer and 1.0°C higher (±1.5°C) in winter across Europe.” Methods Original text: “This resulted in 1248 time series at 1092 locations, extending over the period from 2000 to 2020 and geographically spanning a latitudinal gradient over Europe from Portugal (38.54 N 8.00 W) to Sweden (64.11 N 19.45E) and a longitudinal gradient from Portugal (38.64 N 8.60 W) to Finland (62.33 N 30.37E; Figure S1a). […] We further only selected months with at least 28 days of data, resulting in a cumulative 24,291 months of near-surface air temperature (Table S2).” After correction, more time series, locations and, consequently, more cumulative months became available for our analysis. Hence, the statement above should now read: Corrected text: “This resulted in 1273 time series at 1197 locations, extending over the period from 2000 to 2020 and geographically spanning a latitudinal gradient over Europe from Portugal (38.54 N 8.00 W) to Sweden (64.11 N 19.45E) and a longitudinal gradient from Portugal (38.64 N 8.60 W) to Finland (62.33 N 30.37E; Figure S1a). […] We further only selected months with at least 28 days of data, resulting in a cumulative 25,160 months of near-surface air temperature (Table S2).” Original text: “The offset (∆T) was calculated as the difference between the monthly mean microclimate temperature, as measured by the loggers, and the corresponding monthly mean air temperature value at 2 m height for exactly the same month, year and grid cell from ERA5-Land reanalysis data with a spatial resolution of 0.1 × 0.1 degrees (Muñoz-Sabater et al., 2021).” The offset was calculated in a slightly different manner, matching it with the macroclimate data at a higher temporal resolution (i.e. daily instead of monthly) followed by an aggregation to monthly offset values. Furthermore, we replaced ERA5-Land reanalysis data (i.e. global dataset) to EOBS-based data (i.e. European dataset). Corrected text: “First, we calculated the daily mean temperature offset, which corresponds to the difference between the daily mean microclimate temperature, as measured by the loggers, and the corresponding daily mean air temperature value at 2 m height for exactly the same month, year and grid cell from EOBS data with a spatial resolution of 1 km2 (Cruz-alonso et al., 2022). Moreover, the EOBS data underwent an altitudinal correction according to the lapse rate of that grid cell (Karger et al., 2022). Finally, the daily temperature offset values were aggregated into monthly offset values.” Original text: “Finally, optimal hyperparameter values were selected by maximizing R2CV.” To save time for model predictions, we adopted a trade-off to optimize model performance while reducing computational time. Corrected text: “Finally, optimal hyperparameter values were selected according to the trade-off between model performance (R2CV) and computational time.” Results and Discussion All numbers in the results section were corrected according to the updated results based on the corrected offset values. For this, we refer to the full correction of the article, which can be found in the supplementary materials. Based on the corrected set of values for the response variable of the model (i.e. new ∆T values), the relationships with and the relative importance of the predictor variables slightly changed as well. Therefore, some changes in the main text are made within the section “drivers of microclimate” for which we again refer to the full correction of the article in the supplementary materials. However, one substantial change is worth noting here: Original text: “The interaction between snow cover and sensor height (Figure S3c) clearly hints towards an insulating effect of snow on the sensor which is, contrary to standardised meteorological stations, not kept free of snow or ice.” After correction, the two-way interaction term between snow cover and sensor height was no longer so prominent after correction. However, the three-way interaction term between sensor height, latitude and month was very important and could hint towards the former interaction between sensor height and snow cover but in high-latitude systems only. Corrected text: “Although snow cover is not coming forward as one of the most important covariates, snow is known to be important in driving the temperature offset (Aalto et al., 2018). We expect that the temporal and spatial resolution of this data is too coarse to capture the effect of snow cover. However, the interaction between sensor height, month and latitude (Figure S3b) could hint towards an insulating effect of snow on the sensor which is, contrary to standardised meteorological stations, not kept free of snow or ice.” Supporting Information Filename Description gcb16440-sup-0001-Supinfo.pdfPDF document, 1.3 MB Appendix S1 Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. REFERENCES Cruz-alonso, V., Pucher, C., Ratcliffe, S., Ruiz-benito, P., Astigarraga, J., Neumann, M., Hasenauer, H., & Rodríguez-sánchez, F. (2022). The easyclimate R package: Easy access to high-resolution daily climate data for Europe. https://doi.org/10.32942/osf.io/mc8uj Haesen, S., Lembrechts, J. J., De Frenne, P., Lenoir, J., Aalto, J., Ashcroft, M. B., Kopecký, M., Luoto, M., Maclean, I., Nijs, I., Niittynen, P., van den Hoogen, J., Arriga, N., Brůna, J., Buchmann, N., Čiliak, M., Collalti, A., De Lombaerde, E., Descombes, P., … Van Meerbeek, K. (2021). ForestTemp – Sub-canopy microclimate temperatures of European forests. Global Change Biology, 27(September), 1– 13. https://doi.org/10.1111/gcb.15892 Karger, D. N., Lange, S., Hari, C., Reyer, C. P. O., & Zimmermann, N. E. (2022). CHELSA-W5E5 v1.0: W5E5 v1.0 downscaled with CHELSA v2.0. ISIMIP Repository. https://doi.org/10.48364/ISIMIP.836809.2 Muñoz-Sabater, J., Dutra, E., Agust'í-Panareda, A., Albergel, C., Arduini, G., Balsamo, G., Boussetta, S., Choulga, M., Harrigan, S., Hersbach, H., Martens, B., Miralles, D. G., Piles, M., Rodriguez-Fernandez, N., Zsoter, E., Buontempo, C., & Thépaut, J.-N. (2021). ERA5-land: A state-of-the-art global reanalysis dataset for land applications. Earth System Science Data Discussions, 13, 1– 50. https://doi.org/10.5194/essd-2021-82 Volume28, Issue23December 2022Pages 7157-7158 ReferencesRelatedInformation