Declan O’Donnell
A5046346964- Atmospheric chemistry and aerosols
- Atmospheric aerosols and clouds
- Atmospheric Ozone and Climate
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Vehicle emissions and performance
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Aeolian processes and effects
- Climate Change Policy and Economics
- Methane Hydrates and Related Phenomena
- Distributed and Parallel Computing Systems
- Environmental Policies and Emissions
- Geology and Paleoclimatology Research
- Water Quality and Pollution Assessment
- Advanced Aircraft Design and Technologies
- Cryospheric studies and observations
- Soil and Water Nutrient Dynamics
- Plant responses to elevated CO2
- Marine and coastal ecosystems
- Marine and fisheries research
- Second Language Learning and Teaching
- EFL/ESL Teaching and Learning
- Scientific Computing and Data Management
- Scientific Research and Discoveries
Finnish Meteorological Institute
2014-2024
University of Helsinki
2016
Max Planck Institute for Meteorology
2010-2014
ETH Zurich
2010-2011
Max Planck Society
2010
<strong class="journal-contentHeaderColor">Abstract.</strong> This paper evaluates the current status of global modeling organic aerosol (OA) in troposphere and analyzes differences between models as well observations. Thirty-one chemistry transport (CTMs) general circulation (GCMs) have participated this intercomparison, framework AeroCom phase II. The simulation OA varies greatly terms magnitude primary emissions, secondary (SOA) formation, number species used (2 to 62), complexity...
The Earth system model EC-Earth3 for contributions to CMIP6 is documented here, with its flexible coupling framework, major configurations, a methodology ensuring the simulations are comparable across different high-performance computing (HPC) systems, and physical performance of base configurations over historical period. variety possible sub-models reflects broad interests in EC-Earth community. key metrics demonstrate behavior biases well within frame known from recent CMIP models. With...
Abstract. In this paper we describe and summarize the main achievements of European Aerosol Cloud Climate Air Quality Interactions project (EUCAARI). EUCAARI started on 1 January 2007 ended 31 December 2010 leaving a rich legacy including: (a) comprehensive database with year observations physical, chemical optical properties aerosol particles over Europe, (b) measurements in four developing countries, (c) airborne aerosols clouds Europe during May 2008, (d) modeling tools to study processes...
Abstract. This paper introduces and evaluates the second version of global aerosol-climate model ECHAM-HAM. Major changes have been brought into model, including new parameterizations for aerosol nucleation water uptake, an explicit treatment secondary organic aerosols, modified emission calculations sea salt mineral dust, coupling microphysics to a two-moment stratiform cloud scheme, alternative wet scavenging parameterizations. These revisions extend model's capability represent details...
Abstract. The Earth System Model EC-Earth3 for contributions to CMIP6 is documented here, with its flexible coupling framework, major model configurations, a methodology ensuring the simulations are comparable across different HPC systems, and physical performance of base configurations over historical period. variety possible sub-models reflects broad interests in EC-Earth community. key metrics demonstrate behaviour biases well within frame known from recent CMIP models. With improved...
Abstract. Many modelling groups that contribute to CMIP6 (Coupled Model Intercomparison Project Phase 6) have found a larger equilibrium climate sensitivity (ECS) with their latest model versions compared the values obtained earlier used in CMIP5. This is also case for EC-Earth model. Therefore, this study, we investigate what developments since CMIP5 era could caused increase ECS Apart from increases horizontal and vertical resolution, has substantially changed representation of aerosols;...
Abstract. This paper documents the global climate model EC-Earth3-AerChem, one of members EC-Earth3 family models participating in Coupled Model Intercomparison Project Phase 6 (CMIP6). EC-Earth3-AerChem has interactive aerosols and atmospheric chemistry contributes to Aerosols Chemistry (AerChemMIP). In this paper, we give an overview model, describe detail how it differs from other configurations, outline new features compared with previously documented version (EC-Earth 2.4). We explain...
Abstract. Nucleation from the gas phase is an important source of aerosol particles in Earth's atmosphere, contributing to number cloud condensation nuclei, which form droplets. We have implemented aerosol-climate model ECHAM5-HAM a new scheme for neutral and charged nucleation sulfuric acid water based on laboratory data, organic compound using parametrization cluster activation field measurements. give details implementation, compare results with observations, investigate role individual...
Abstract. Secondary organic aerosol (SOA) has been introduced into the global climate-aerosol model ECHAM5/HAM. The SOA module handles aerosols originating from both biogenic and anthropogenic sources. simulates emission of precursor gases, their chemical conversion condensable partitioning semi-volatile condenable species gas phases. As ECHAM5/HAM is a size-resolved model, new method that permits calculation between different size classes introduced. We compare results modelled...
Abstract. Changes in anthropogenic aerosol emissions have strongly contributed to global and regional trends temperature, precipitation, other climate characteristics been one of the dominant drivers decadal Asian African precipitation. These influences on from changes are expected continue potentially strengthen coming decades. However, a combination large uncertainties emission pathways, radiative forcing, dynamical response forcing makes key factor spread near-term projections,...
Abstract. This study assesses the change in anthropogenic aerosol forcing from mid-1970s to mid-2000s. Both decades had similar global-mean optical depths but substantially different global distributions. For both years, we quantify (i) spread due model-internal variability and (ii) among models. Our assessment is based on new ensembles of atmosphere-only simulations with five state-of-the-art Earth system Four these models will be used sixth Coupled Model Intercomparison Project (CMIP6;...
Abstract. Biogenic volatile organic compounds (BVOCs) emitted from vegetation are oxidised in the atmosphere and can form aerosol particles either by contributing to new particle formation or condensing onto existing particles. As understanding of importance BVOCs for has increased over years, these processes have made their way into Earth system models (ESMs). In this study, sensitivity experiments run with three different ESMs (the Norwegian System Model (NorESM), EC-Earth ECHAM)...
<title>Abstract</title> Global surface warming has accelerated since around 2010, relative to the preceding half century<sup>1-3</sup>. This coincided with China’s efforts reduce air pollution through restricted atmospheric aerosol and precursor emissions<sup>4,5</sup>. A direct link between two has, however, not yet been established. Here we show, using a large set of simulations from eight Earth System Models, how time evolving 75% reduction in Chinese sulfate emissions partially unmasks...
Abstract. Many modelling groups that contribute to CMIP6 (Coupled Model Intercomparison Project phase 6) have found a larger equilibrium climate sensitivity (ECS) with their latest model versions compared the values obtained earlier for CMIP5. This is also case EC-Earth model, and in this study we investigate what developments since CMIP5 era could caused increase ECS model. Apart from increases horizontal vertical resolution, has substantially changed representation of aerosols, particular...
To assess the impact of anthropogenic aerosol emission reduction on limiting global temperature increase to 1.5 °C or 2 above pre-industrial levels, two climate modeling approaches have been used (MAGICC6, and a combination ECHAM-HAMMOZ UVic ESCM), with control pathways under greenhouse gas (GHG) scenarios. We found that reductions associated CO2 co-emissions had significant warming effect during first half century near-term is dependent pace reduction. The results show these account for...
Abstract. The mineral dust cycle responds to climate variations and plays an important role in the system by affecting radiative balance of atmosphere modifying biogeochemistry. Polar ice cores provide unique information about deposition aeolian particles transported over long distances. These are a palaeoclimate proxy archive variability thousands years ago. current study is first attempt simulate past interglacial cycles with global aerosol–climate model ECHAM5-HAM. results used explain...
Abstract. REMO-HAM is a new regional aerosol-climate model. It based on the REMO climate model and includes most of major aerosol processes. The structure for similar to global ECHAM5-HAM, example module HAM coupled with two-moment stratiform cloud scheme. On other hand, does not include an online aerosol-radiation nor secondary organic module. In this work, we evaluate compare results against ECHAM5-HAM measurements. Four different measurement sites were chosen comparison total number...
Abstract. This paper introduces and evaluates the second version of global aerosol-climate model ECHAM-HAM. Major changes have been brought into model, including new parameterizations for aerosol nucleation water uptake, an explicit treatment secondary organic aerosols, modified emission calculations sea salt mineral dust, coupling microphysics to a two-moment stratiform cloud scheme, alternative wet scavenging parameterizations. These revisions extend model's capability represent details...
Abstract. Significant discrepancies remain in estimates of climate impacts anthropogenic aerosols between different general circulation models (GCMs). Here, we demonstrate that eliminating differences model aerosol or radiative forcing fields results close agreement simulated globally averaged temperature and precipitation responses the studied GCMs. However, it does not erase regional responses. We carry out experiments equilibrium response to modern-day using an identical representation...
Abstract. This paper documents the global climate model EC-Earth3-AerChem, one of members EC-Earth3 family models participating in Coupled Model Intercomparison Project phase 6 (CMIP6). EC-Earth3-AerChem has interactive aerosols and atmospheric chemistry contributes to Aerosols Chemistry (AerChemMIP). In this paper, we give an overview describe detail how it differs from other configurations, what new features are compared previously documented version (EC-Earth 2.4). We explain was tuned...
Abstract Simple mass balance models have been frequently used in limnology to study the retention of nutrients by lakes. However, there are difficulties applying marine systems, particularly with regard parameters involved tidal flushing. A well defined channel at entrance Lough Hyne allows use adapted nutrient economy, and make inferences about system scale productivity. Water quality gathered over four years demonstrated a net input lough for three different nutrients. There was dissolved...
Abstract. South and East Asian anthropogenic aerosols mostly reside in an air mass extending from the Indian Ocean to North Pacific. Yet surface temperature effects of spread across whole globe. Here, we remove two independent climate models (ECHAM6.1 NorESM1) using same representation via MACv2-SP (a simple plume implementation second version Max Planck Institute Aerosol Climatology). We then robustly decompose global distribution responses into contributions atmospheric energy flux...
Abstract. This paper evaluates the current status of global modeling organic aerosol (OA) in troposphere and analyzes differences between models as well observations. Thirty-one chemistry/transport general circulation have participated this intercomparison, framework AeroCom phase II. The simulation OA varies greatly terms magnitude primary emissions, secondary (SOA) formation, number species used (2 to 62), complexity parameterizations (gas-particle partitioning, chemical aging, multiphase...
Abstract. In this paper we describe and summarize the main achievements of European Aerosol Cloud Climate Air Quality Interactions project (EUCAARI). EUCAARI started on 1 January 2007 ended 31 December 2010 leaving a rich legacy including: (a) comprehensive database with year observations physical, chemical optical properties aerosol particles over Europe, (b) first measurements in four developing countries, (c) airborne aerosols clouds Europe during May 2008, (d) modeling tools to study...