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There are significant pressures from climate change and air pollution that forests currently face. This book aims to increase understanding of the state and potential of forest ecosystems to mitigate and adapt to climate change in a polluted environment. It reconciles process-oriented research, long-term monitoring and applied modeling through comprehensive forest ecosystem research. Furthermore, it introduces ""forest super sites for research? for integrating soil, plant and atmospheric sciences and monitoring. It also provides mechanistic and policy-oriented modeling with scientifically sound

78 páginas,7 tablas, 11 figuras. ; The DO3SE (Deposition of O3 for Stomatal Exchange) model is an established tool for estimating ozone (O3 ) deposition, stomatal flux and impacts to a variety of vegetation types across Europe. It has been embedded within the EMEP (European Monitoring 5 and Evaluation Programme) photochemical model to provide a policy tool capable of relating the risk of vegetation damage to O3 precursor emission scenarios for use in policy formulation. A key limitation of regional flux-based risk assessments so far has been the approximation that soil water deficits are not limiting O3 flux due to the unavailability of evaluated methods for modelling soil water deficits and their influence on stomatal conductance (gsto 10 ), and ultimately O3 flux. This paper describes the development and evaluation of a method to estimate soil moisture status and its influence on gsto for a variety of forest tree species. The soil moisture module uses the Penman-Monteith energy balance method to drive water cycling through the soil-plant-atmosphere system and empirical data describing gsto 15 relationships with pre-dawn leaf water status to estimate the biological control of transpiration. We trial four different methods to estimate this biological control of the transpiration stream, which vary from simple methods that relate soil water content or potential directly to gsto to more complex methods that incorporate hydraulic resistance and plant capacitance that control water flow through the plant system. 20 These methods are evaluated against field data describing a variety of soil water variables, gsto and transpiration data for Norway spruce (Picea abies), Scots pine (Pinus sylvestris), birch (Betula pendula), aspen (Populus tremuloides), beech (Fagus sylvatica) and holm oak (Quercus ilex) collected from ten sites across Europe and North America. Modelled estimates of these variables show consistency with observed 25 data when applying the simple empirical methods, with the timing and magnitude of soil drying events being captured well across all sites and reductions in transpiration with the onset of drought being predicted with reasonable accuracy. The more complex methods which incorporate hydraulic resistance and plant capacitance perform less well, with predicted drying cycles consistently underestimating the rate and magnitude of water lost from the soil. A sensitivity analysis showed that model performance was strongly dependent upon the local parameterisation of key model drivers such as the maximum stomatal conduc- 5 tance, soil texture, root depth and leaf area index. The results suggest that the simple modelling methods that relate gsto directly to soil water content and potential provide adequate estimates of soil moisture and influence on gsto such that they are suitable to be used to assess the potential risk posed by O3 to forest trees across Europe. ; We acknowledge the UK Department of Food and Rural Affairs (Defra) under contract AQ 601 who provided support for this research, as well as funding from the EU Nitro-Europe project (www.nitroeurope.eu) and EMEP under UNECE.R. Alonso would like to 25 thank for the financial support from the Spanish projects Consolider Montes CSD2008-00040, CGL2009-13188-C03-02 and CAM-Agrisost ; Peer reviewed

ESA ; CNES (France) ; CNRS/INSU-IN2P3-INP (France) ; ASI (Italy) ; CNR (Italy) ; INAF (Italy) ; NASA (USA) ; DoE (USA) ; STFC (UK) ; UKSA (UK) ; CSIC (Spain) ; MINECO (Spain) ; JA (Spain) ; RES (Spain) ; Tekes (Finland) ; AoF (Finland) ; CSC (Finland) ; DLR (Germany) ; MPG (Germany) ; CSA (Canada) ; DTU Space (Denmark) ; SER/SSO (Switzerland) ; RCN (Norway) ; SFI (Ireland) ; FCT/MCTES (Portugal) ; ERC (EU) ; PRACE (EU) ; UK BIS NEI grants ; Office of Science of the U.S. Department of Energy ; Canada Foundation for Innovation under Compute Canada ; Government of Ontario ; University of Toronto ; Science and Technology Facilities Council ; Office of Science of the U.S. Department of Energy: DE-AC02-05CH11231 ; Science and Technology Facilities Council: ST/L000768/1 ; Science and Technology Facilities Council: ST/L000652/1 ; Science and Technology Facilities Council: ST/J005673/1 ; Science and Technology Facilities Council: ST/M00418X/1 ; Science and Technology Facilities Council: ST/L000393/1 ; Science and Technology Facilities Council: ST/M007065/1 ; Science and Technology Facilities Council: ST/K00333X/1 ; The Planck full mission cosmic microwave background (CMB) temperature and E-mode polarization maps are analysed to obtain constraints on primordial non-Gaussianity (NG). Using three classes of optimal bispectrum estimators - separable template-fitting (KSW), binned, and modal we obtain consistent values for the primordial local, equilateral, and orthogonal bispectrum amplitudes, quoting as our final result from temperature alone f(NL)(local) = 2.5 +/- 5.7, f(NL)(equil) = 16 +/- 70, and f(NL)(ortho) = 34 +/- 33 (68% CL, statistical). Combining temperature and polarization data we obtain f(NL)(local) = 0.8 +/- 5.0, f(NL)(equil) = 4 +/- 43, and f(NL)(ortho) = 26 +/- 21 (68% CL, statistical). The results are based on comprehensive cross-validation of these estimators on Gaussian and non-Gaussian simulations, are stable across component separation techniques, pass an extensive suite of tests, and are consistent with estimators based on measuring the Minkowski functionals of the CMB. The effect of time-domain de-glitching systematics on the bispectrum is negligible. In spite of these test outcomes we conservatively label the results including polarization data as preliminary, owing to a known mismatch of the noise model in simulations and the data. Beyond estimates of individual shape amplitudes, we present model-independent, three-dimensional reconstructions of the Planck CMB bispectrum and derive constraints on early universe scenarios that generate primordial NG, including general single-field models of inflation, axion inflation, initial state modifications, models producing parity-violating tensor bispectra, and directionally dependent vector models. We present a wide survey of scale-dependent feature and resonance models, accounting for the look elsewhere effect in estimating the statistical significance of features. We also look for isocurvature NG, and find no signal, but we obtain constraints that improve significantly with the inclusion of polarization. The primordial trispectrum amplitude in the local model is constrained to be g(NL)(local) = (9.0 +/- 7.7) x 10(4) (68% CL statistical), and we perform an analysis of trispectrum shapes beyond the local case. The global picture that emerges is one of consistency with the premises of the Lambda CDM cosmology, namely that the structure we observe today was sourced by adiabatic, passive, Gaussian, and primordial seed perturbations.

The following authors were omitted from the original version of this Data Descriptor: Markus Reichstein and Nicolas Vuichard. Both contributed to the code development and N. Vuichard contributed to the processing of the ERA-Interim data downscaling. Furthermore, the contribution of the co-author Frank Tiedemann was re-evaluated relative to the colleague Corinna Rebmann, both working at the same sites, and based on this re-evaluation a substitution in the co-author list is implemented (with Rebmann replacing Tiedemann). Finally, two affiliations were listed incorrectly and are corrected here (entries 190 and 193). The author list and affiliations have been amended to address these omissions in both the HTML and PDF versions. © 2021, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.