David A. Plummer
A5022921592- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Astronomical Observations and Instrumentation
- Climate variability and models
- Calibration and Measurement Techniques
- Astronomy and Astrophysical Research
- Air Quality Monitoring and Forecasting
- Air Quality and Health Impacts
- Sensor Technology and Measurement Systems
- Scientific Measurement and Uncertainty Evaluation
- Astrophysical Phenomena and Observations
- Methane Hydrates and Related Phenomena
- Ocean Acidification Effects and Responses
- Meteorological Phenomena and Simulations
- Ionosphere and magnetosphere dynamics
- Adaptive optics and wavefront sensing
- Climate Change and Health Impacts
- Stellar, planetary, and galactic studies
- Advanced Measurement and Metrology Techniques
- Magnetic confinement fusion research
- Fire effects on ecosystems
- Atmospheric aerosols and clouds
- Particle Detector Development and Performance
- Nuclear reactor physics and engineering
Environment and Climate Change Canada
2015-2024
Center for Astrophysics Harvard & Smithsonian
2012-2018
University of Victoria
2008-2018
Climate Centre
2008-2017
Culham Science Centre
2014-2015
Culham Centre for Fusion Energy
2014
Pacific Institute for Climate Solutions
2010-2014
Goddard Institute for Space Studies
2012
Met Office
2012
National Institute for Environmental Studies
2012
<strong class="journal-contentHeaderColor">Abstract.</strong> Present day tropospheric ozone and its changes between 1850 2100 are considered, analysing 15 global models that participated in the Atmospheric Chemistry Climate Model Intercomparison Project (ACCMIP). The ensemble mean compares well against present observations. seasonal cycle correlates well, except for some locations tropical upper troposphere. Most (75 %) of encompassed with a range column estimates from satellite data, but...
Simulations of the stratosphere from thirteen coupled chemistry‐climate models (CCMs) are evaluated to provide guidance for interpretation ozone predictions made by same CCMs. The focus evaluation is on how well fields and processes that important determining distribution represented in simulations recent past. core period 1980 1999 but long‐term trends compared an extended (1960–2004). Comparisons polar high‐latitude temperatures show most CCMs have only small biases Northern Hemisphere...
Increased concentrations of ozone and fine particulate matter (PM2.5) since preindustrial times reflect increased emissions, but also contributions past climate change. Here we use modeled from an ensemble chemistry–climate models to estimate the global burden anthropogenic outdoor air pollution on present-day premature human mortality, component that attributable Using simulated for 2000 1850 concentration–response functions (CRFs), that, at present, 470 000 (95% confidence interval, 140...
Abstract. The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) consists of a series time slice experiments targeting the long-term changes in atmospheric composition between 1850 2100, with goal documenting associated radiative forcing. In this overview paper, we introduce ACCMIP activity, various simulations performed (with requested set 14) model output. 16 models have wide range horizontal vertical resolutions, extent, chemistry schemes interaction radiation...
Abstract. Ozone (O3) from 17 atmospheric chemistry models taking part in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) has been used to calculate tropospheric ozone radiative forcings (RFs). All applied a common set of anthropogenic emissions, which are better constrained for present-day than past. Future emissions follow four Representative Concentration Pathway (RCP) scenarios, define relatively narrow range possible air pollution emissions. We value...
Abstract. The Canadian Centre for Climate Modelling and Analysis third generation atmospheric general circulation model (AGCM3) is described. discussion summarizes the details of complete physics package emphasizing changes made relative to second version model. AGCM3 underlying applications which include IPCC fourth assessment, coupled atmosphere-ocean seasonal forecasting, first CCCma earth system (CanESM1), middle-atmosphere chemistry-climate modelling (CCM). Here we shall focus on issues...
The goal of the Tropospheric Ozone Assessment Report (TOAR) is to provide research community with an up-to-date scientific assessment tropospheric ozone, from surface tropopause. While a suite observations provides significant information on spatial and temporal distribution observational gaps make it necessary use global atmospheric chemistry models synthesize our understanding processes variables that control ozone abundance its variability. Models facilitate interpretation allow us...
Abstract. We present an overview of state-of-the-art chemistry–climate and chemistry transport models that are used within phase 1 the Chemistry–Climate Model Initiative (CCMI-1). The CCMI aims to conduct a detailed evaluation participating using process-oriented diagnostics derived from observations in order gain confidence models' projections stratospheric ozone layer, tropospheric composition, air quality, where applicable global climate change, interactions between them. Interpretation...
Abstract. We have analysed time-slice simulations from 17 global models, participating in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), to explore changes present-day (2000) hydroxyl radical (OH) concentration methane (CH4) lifetime relative preindustrial times (1850) 1980. A comparison of modeled observation-derived methyl chloroform lifetimes suggests that multi-model mean OH is overestimated by 5 10% but within range uncertainties. The models consistently...
Simulations from eleven coupled chemistry‐climate models (CCMs) employing nearly identical forcings have been used to project the evolution of stratospheric ozone throughout 21st century. The model‐to‐model agreement in projected temperature trends is good, and all CCMs predict continued, global mean cooling stratosphere over next 5 decades, increasing around 0.25 K/decade at 50 hPa 1 under Intergovernmental Panel on Climate Change (IPCC) Special Report Emissions Scenarios (SRES) A1B...
Abstract. We present multi-model global datasets of nitrogen and sulfate deposition covering time periods from 1850 to 2100, calculated within the Atmospheric Chemistry Climate Model Intercomparison Project (ACCMIP). The computed fluxes are compared surface wet ice core measurements. use a new dataset for 2000–2002 based on critical assessment quality existing regional network data. show that day (year 2000 ACCMIP slice), results perform similarly previously published assessments. For this...
The Canadian Centre for Climate Modelling and Analysis (CCCma) has developed the fourth generation of Atmospheric Global Model (CanAM4). new model includes substantially modified physical parameterizations compared to its predecessor. In particular, treatment clouds, cloud radiative effects, precipitation been modified. Aerosol direct indirect effects are calculated based on a bulk aerosol scheme. Simulation results present-day global climate analyzed, with focus precipitation. Good overall...
The impact of stratospheric ozone on the tropospheric general circulation Southern Hemisphere (SH) is examined with a set chemistry‐climate models participating in Stratospheric Processes and their Role Climate (SPARC)/Chemistry‐Climate Model Validation project phase 2 (CCMVal‐2). integrations both past future climates reveal crucial role driving SH change: stronger depletion late spring generally leads to greater poleward displacement intensification midlatitude jet, expansion Hadley cell...
Abstract. Results from simulations performed for the Atmospheric Chemistry and Climate Modeling Intercomparison Project (ACCMIP) are analysed to examine how OH methane lifetime may change present day future, under different climate emissions scenarios. Present (2000) mean tropospheric chemical derived ACCMIP multi-model is 9.8 ± 1.6 yr (9.3 0.9 when only including selected models), lower than a recent observationally-based estimate, but with similar range previous estimates. Future model...
Abstract The response of stratospheric climate and circulation to increasing amounts greenhouse gases (GHGs) ozone recovery in the twenty-first century is analyzed simulations 11 chemistry–climate models using near-identical forcings experimental setup. In addition an overall global cooling stratosphere (0.59 ± 0.07 K decade−1 at 10 hPa), causes a warming Southern Hemisphere polar lower summer with enhanced above. rate correlates projected by and, on average, changes from 0.8 0.48 100 hPa as...
The Chandra Source Catalog (CSC) is a general purpose virtual X-ray astrophysics facility that provides access to carefully selected set of generally useful quantities for individual sources, and designed satisfy the needs broad-based group scientists, including those who may be less familiar with astronomical data analysis in regime. first release CSC includes information about 94,676 distinct sources detected subset public ACIS imaging observations from roughly eight years mission. This...
Abstract The separate effects of ozone depleting substances (ODSs) and greenhouse gases (GHGs) on forcing circulation changes in the Southern Hemisphere extratropical troposphere are investigated using a version Canadian Middle Atmosphere Model (CMAM) that is coupled to an ocean. Circulation-related diagnostics include zonal wind, tropopause pressure, Hadley cell width, jet location, annular mode index, precipitation, wave drag, eddy fluxes momentum heat. As expected, tropospheric response...
Our understanding of the processes that control burden and budget tropospheric ozone has changed dramatically over last 60 years. Models are key tools used to understand these changes, underscore there many important in controlling budget. In this critical review, we assess our evolving processes, both physical chemical. We review model simulations from International Global Atmospheric Chemistry Climate Model Intercomparison Project Modelling Initiative changes its 1850 2010. Analysis data...
Abstract. >We analyse simulations performed for the Chemistry-Climate Model Initiative (CCMI) to estimate return dates of stratospheric ozone layer from depletion caused by anthropogenic chlorine and bromine. We consider a total 155 20 models, including range sensitivity studies which examine impact climate change on recovery. For control (unconstrained nudging towards analysed meteorology) there is large spread (±20 DU in global average) predictions absolute column. Therefore, model...
Abstract An analysis of several multidecadal simulations the present (1971–90) and future (2041–60) climate from Canadian Regional Climate Model (CRCM) is presented. The effects on CRCM model domain size, internal variability general circulation (GCM) used to provide boundary conditions, modifications physical parameterizations in are investigated. influence conditions further investigated by comparing GCM-driven current with performed using meteorological reanalyses. these different...
The performance of 18 coupled Chemistry Climate Models (CCMs) in the Tropical Tropopause Layer (TTL) is evaluated using qualitative and quantitative diagnostics. Trends tropopause quantities tropics extratropical Upper Troposphere Lower Stratosphere (UTLS) are analyzed. A grading methodology for evaluating CCMs extended to include variability used develop four different grades tropical temperature pressure, water vapor ozone. Four models multi‐model mean meet standards reproducing key...
Abstract. Projections of stratospheric ozone from a suite chemistry-climate models (CCMs) have been analyzed. In addition to reference simulation where anthropogenic halogenated depleting substances (ODSs) and greenhouse gases (GHGs) vary with time, sensitivity simulations either ODS or GHG concentrations fixed at 1960 levels were performed disaggregate the drivers projected changes. These also used assess two distinct milestones returning historical values (ozone return dates) no longer...
[1] The stratospheric climate and variability from simulations of sixteen chemistry-climate models is evaluated. On average the polar night jet well reproduced though its less with a large spread between models. Polar temperature biases are than 5 K except in Southern Hemisphere (SH) lower stratosphere spring. accumulated area low temperatures responsible for cloud formation accurately Antarctic but underestimated Arctic. shape position vortex simulated, as tropical upwelling stratosphere....