Leaf chlorophyll is central to the exchange of carbon, water and energy between the biosphere and the atmosphere, and to the functioning of terrestrial ecosystems. This paper presents the first spatially continuous view of terrestrial leaf chlorophyll content (ChlLeaf) across a global scale. Weekly maps of ChlLeaf were produced from ENIVSAT MERIS full resolution (300 m) satellite data with a two-stage physically-based radiative transfer modelling approach. Firstly, leaf-level reflectance was derived from top-of-canopy satellite reflectance observations using 4-Scale and SAIL canopy radiative transfer models 3 for woody and non-woody vegetation, respectively. Secondly, the modelled leaf-level reflectance was used in the PROSPECT leaf-level radiative transfer model to derive ChlLeaf. The ChlLeaf retrieval algorithm was validated with measured ChlLeaf data from sample measurements at field locations, and covering six plant functional types (PFTs). Modelled results show strong relationships with field measurements, particularly for deciduous broadleaf forests (R 2 = 0.67; RMSE = 9.25 µg cm -2 ; p<0.001), croplands (R 2 = 0.41; RMSE = 13.18 µg cm -2 ; p<0.001) and evergreen needleleaf forests (R 2 = 0.47; RMSE = 10.63 µg cm -2 ; p<0.001). When the modelled results from all PFTs were considered together, the overall relationship with measured ChlLeaf remained good (R 2 = 0.47, RMSE = 10.79 µg cm -2 ; p<0.001).This result was an improvement on the relationship between measured ChlLeaf and a commonly used chlorophyll-sensitive spectral vegetation index; the MERIS Terrestrial Chlorophyll Index (MTCI; R 2 = 0.27, p<0.001). The global maps show large temporal and spatial variability in ChlLeaf, with evergreen broadleaf forests presenting the highest leaf chlorophyll values with global annual median of 54.4 µg cm -2 . Distinct seasonal ChlLeaf phenologies are also visible, particularly in deciduous plant forms, associated with budburst and crop growth, and leaf senescence. It is anticipated that this global ChlLeaf product will make an important step towards the explicit consideration of leaf-level biochemistry in terrestrial water, energy and carbon cycle modelling.

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Terrestrial ecosystems of Canada store a large amount of organic carbon (C) in soils, peats and plant materials, yet little is known about the C stock size and distributions, both spatially and in various C pools. As temperature rises, C is becoming available for disturbance, decomposition and eventual release into the atmosphere, which makes the quantification of C stocks in terrestrial ecosystems of Canada of high interest for the assessment of climate change impacts and conservation efforts. We used a large number of field measurements, multisource satellite, climate and topographic data and a machine learning algorithm to produce the first wall‐to‐wall estimates of C stocks and uncertainties in plants and soils of Canada at 250 m spatial resolution. Our findings show that above and belowground live biomass and detritus store a total of 21.1 Pg of carbon (Pg C). Whereas the Canadian soils store 306 (±147, 90% confidence interval) Pg organic C in the top 1 m, 98 Pg C of which are stored in peatlands, confirming that the soil organic C dominates terrestrial carbon stocks in Canada. We also find previously under‐reported large soil organic C stocks in forested peatlands on the boreal shields of Canada. Given that Canada is warming twice the global average rate and Canadian soils store approximately 20.4% of world soil C stocks in top 1 m, initiatives to understand their vulnerabilities to climate change and disturbance are indispensable not only for Canada but also for the global C cycle.

Previous research has suggested that Type A, compared to Type B patients undergoing coronary artery bypass surgery evidence greater intraoperative increases over hospital admission systolic blood pressure, even though patients are under general anesthesia. The present study sought to examine whether such blood pressure increases are accounted for by elevations occurring entirely during surgery (with conscious mediation minimized), or by increases occurring prior to surgery. A second purpose of the study was to examine the relationship between Type A behavior and complications occurring during and after surgery. Twenty-seven male patients given a structured interview to measure Type A behavior in advance of surgery comprised the present sample. Results indicated that interview Type A intensity was reliably related to magnitude of systolic, but not diastolic blood pressure increases during, but not prior to surgery. The 12 patients with complications (largely arrhythmias), were reliably higher in rated intensity of Type A behavior (p less than 0.01) than those without complications (n = 14). None of the Type B or Type X patients showed evidence of complications during or after surgery. Results of this study support a body of data linking Type A behavior to cardiovascular reactivity and clinical complications of coronary disease. Since this reactivity is evident under general anesthesia, these data further suggest that conscious mediation may not always be necessary in order to elicit these responses.