A5088273507- Cryospheric studies and observations
- Plant Water Relations and Carbon Dynamics
- Climate change and permafrost
- Climate variability and models
- Forest ecology and management
- Hydrology and Watershed Management Studies
- Tree-ring climate responses
- Atmospheric and Environmental Gas Dynamics
- Remote Sensing in Agriculture
- Fire effects on ecosystems
- Meteorological Phenomena and Simulations
- Plant responses to elevated CO2
- Peatlands and Wetlands Ecology
- Soil and Unsaturated Flow
- Landslides and related hazards
- Soil Moisture and Remote Sensing
- Arctic and Antarctic ice dynamics
- Chemical Synthesis and Analysis
- Animal Vocal Communication and Behavior
- Avian ecology and behavior
- Animal Behavior and Reproduction
- Vehicle emissions and performance
- Species Distribution and Climate Change
- Astro and Planetary Science
- Forest Management and Policy
Environment and Climate Change Canada
2012-2021
University of Edinburgh
2021
Ministry of the Environment, Conservation and Parks
2017
Cranfield University
2007
Metric Systems Corporation (United States)
2004
Trent University
1999
Queen's University
1999
Improving the accuracy of estimates forest carbon exchange is a central priority for understanding ecosystem response to increased atmospheric CO2 levels and improving cycle modelling. However, spatially continuous parameterization photosynthetic capacity (Vcmax) at global scales appropriate temporal intervals within terrestrial biosphere models (TBMs) remains unresolved. This research investigates use biochemical parameters modelling leaf deciduous forest. Particular attention given impacts...
Thirty‐three snowpack models of varying complexity and purpose were evaluated across a wide range hydrometeorological forest canopy conditions at five Northern Hemisphere locations, for up to two winter snow seasons. Modeled estimates water equivalent (SWE) or depth compared observations open sites each location. Precipitation phase duration above‐freezing air temperatures are shown be major influences on divergence convergence modeled the subcanopy snowpack. When considered collectively all...
The Northern Hemisphere has large areas that are forested and seasonally snow covered. Compared with open areas, forest canopies strongly influence interactions between the atmosphere on ground by sheltering from wind solar radiation intercepting falling snow; these influences have important consequences for meteorology, hydrology, ecology of forests. Many land surface models used in meteorological hydrological forecasting now include representations canopy processes, but not been widely...
Abstract. This paper describes ESM-SnowMIP, an international coordinated modelling effort to evaluate current snow schemes, including schemes that are included in Earth system models, a wide variety of settings against local and global observations. The project aims identify crucial processes characteristics need be improved models the context local- global-scale modelling. A further objective ESM-SnowMIP is better quantify snow-related feedbacks system. Although it not part sixth phase...
Abstract Twenty-seven models participated in the Earth System Model–Snow Model Intercomparison Project (ESM-SnowMIP), most data-rich MIP dedicated to snow modeling. Our findings do not support hypothesis advanced by previous MIPs: evaluating against more variables and providing evaluation datasets extended temporally spatially does facilitate identification of key new processes requiring improvement model mass energy budgets, even at point scales. In fact, same modeling issues identified...
Purpose – This paper seeks to investigate the links between different types of visibility, joint initiatives and business performance using concepts transparency as a measure visibility in supply chains. The prognosis that increased chain can be achieved through suppliers customers working on initiative(s), deployment which leads collaborative successes, is tested.
Abstract Version 3.1 of the Canadian Land Surface Scheme (CLASS) contains a number new algorithms significance for snow simulations in boreal forest. In particular, mixed precipitation is now modelled, density fresh varies with temperature and maximum snowpack depth. A model canopy interception unloading developed forest has also been implemented. this paper, nine‐month column runs CLASS are compared 2.7, current operational version. The span winter 2002–03 at three sites: mature aspen...
Abstract Snow accumulation and melt were observed at shrub tundra sites in the western Canadian Arctic. End of winter snow water equivalent (SWE) was higher site than site, but lower total snowfall because removed by blowing snow, a component also lost to sublimation. Removal from larger expected shrubs bent over covered during much winter. Although SWE disappeared similar time both sites, suggesting enhanced site. The Land Surface Scheme (CLASS) used explore processes controlling this melt....
Abstract. This paper describes in situ meteorological forcing and evaluation data, bias-corrected reanalysis for cold regions' modelling at 10 sites. The long-term datasets (one maritime, one arctic, three boreal, five mid-latitude alpine) are the reference sites chosen evaluating models participating Earth System Model-Snow Model Intercomparison Project. Periods covered by data vary between 7 20 years of hourly with (snow depth, snow water equivalent, albedo, soil temperature, surface...
Micrometeorological measurements were made over a northern boreal fen near Thompson, Manitoba, Canada, as part of the Boreal Ecosystem‐Atmosphere Study. The measurement period extended from start snowmelt until early fall, at which time senescence was widespread throughout fen. Data analysis concentrated on identifying seasonal trends in energy, water, and carbon dioxide fluxes linking them to observed surface cover changes. Albedos (solar photosynthetically active radiation (PAR)) showed...
Abstract. Leaf area index (LAI) and its seasonal dynamics are key determinants of vegetation productivity in nature as represented terrestrial biosphere models seeking to understand land surface atmosphere flux response climate change. Non-structural carbohydrates (NSCs) their variability known play a crucial role variation leaf phenology growth functioning plants. The carbon stored NSC pools provides buffer during times when supply demand asynchronous. An example this is illustrated NSCs...
Climatological measurements, including carbon dioxide flux density, were made from April to September in 1994 and November 1996 at a fen wetland near Thompson, Manitoba, Canada, as part of the Boreal Ecosystem‐Atmosphere Study (BOREAS). For both years, study period was warmer drier than 24‐year climate normals. The CO 2 uptake similar for reaching maximum measured assimilation rates −0.55 mg m −2 s −1 midsummer. However, air temperatures an earlier snowmelt spring 1994, which led thaw...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEster-enolate Claisen rearrangement of .alpha.-amino acid derivativesPaul A. Bartlett and James F. BarstowCite this: J. Org. Chem. 1982, 47, 20, 3933–3941Publication Date (Print):September 1, 1982Publication History Published online1 May 2002Published inissue 1 September 1982https://pubs.acs.org/doi/10.1021/jo00141a024https://doi.org/10.1021/jo00141a024research-articleACS PublicationsRequest reuse permissionsArticle...
Abstract An evaluation of the Canadian Land Surface Scheme (CLASS) 3.1 snow cover simulations at four sites included in Snow Model Intercomparison Project (SnowMIP) revealed that CLASS was able to provide realistic representations accumulation, melt and physical properties over a range climates. The modified aging parametrization provided improved snowpack density which resulted marked reduction root‐mean‐square (rms) error for daily depth, slight improvements surface temperature. still...
Abstract This study investigates the role of leaf/plant area index (LAI / PAI) specification on large spread winter albedo simulated by climate models. To examine sensitivity to LAI, we perform a analysis using two methods commonly used compute in snow‐covered forests as well diagnostic calculations within version 4.2 Canadian Atmospheric Model for which PAI is systematically varied. The results show that very sensitive negative biases, especially smaller values. LAI and surface boreal...
Abstract. Our study evaluates the impacts of an alternate snow cover fraction (SCF) parameterization on simulation in Canadian Land Surface Scheme Including Biogeochemical Cycles (CLASSIC). Three reanalysis-based meteorological datasets are used to drive model account for uncertainties forcing data. While default assumes a simple linear relationship between SCF and depth with no dependence topography, accounts topographic effects sub-grid terrain SCF. We show that improves simulated CLASSIC...
Seasonal patterns of the energy balance a young jack pine site near Thompson, Manitoba, in summer 1994 are reported. The experiment was part Boreal Ecosystem‐Atmosphere Study (BOREAS), and it ran from May 24 to September 19. average tree density 4.4 trees m −2 , but there substantial spatial variation associated with three primary vegetation patterns: dense cover short trees, sparse tall mixture trees. frequency distribution heights bimodal peaks at 1 2 range 0.3 5.7 m. height 2.3 daily...
The Canadian Land Surface Scheme (CLASS) was modified to correct an underestimation of the winter albedo in evergreen needleleaf forests. Default values for visible and near-infrared a canopy with intercepted snow, αVIS,cs αNIR,cs, respectively, were too small, fraction covered fsnow, increased slowly interception, producing damped response. A new model fsnow is based on zI*, effective depth newly snow required increase its maximum, which corresponds = 1. Snow unloading rates extracted from...
Abstract. The 30-year simulations of seasonal snow cover in 22 physically based models driven with bias-corrected meteorological reanalyses are examined at four sites long records observations. Annual durations differ widely between models, but interannual variations strongly correlated because the common driving data. No significant trends observed starting dates for cover, there towards ending earlier two observations and most models. A simplified model just parameters controlling solar...
Abstract Die Synthese des aminosubstituierten Triarylphosphin‐Liganden Tris‐[p‐(aminomethyl)‐phenyl]‐phosphin, der als Tris‐tosylat (IV) nach dem aufgezeigten Schema ausgehend von Diacetal (I) gebildet und isoliert wird, ermöglicht die Darstellung wasserlöslichen Undecagold‐Cluster (VIII).
The DayCENT model was employed to simulate the effects of conventional tillage (CT) and no‐till (NT) practices on dynamics soil organic carbon (SOC) over 9 yr in a rotational cropping system Southern Ontario, Canada. Observations site properties eddy covariance measurements were used assess crop productivity, net ecosystem productivity (NEP), SOC changes. validated captured grain yield primary production, which indicated that can be for evaluating residues heterotrophic respiration ( R h )...
A new individual with a different social call was introduced into each of three flocks male budgerigars in which the birds were well-established and shared their call. The calls monitored over ensuing 53 days compared using cross-correlational analyses based on SIGNAL software system. In all cases bird changed to conform that group without marked changes others. major change took place approximately 15–30 after introduction bird. It is suggested relations determine occur groups.