Air pollutants: Regional transport, properties and effect on upper tropospheric humidity

Research output: ThesisDoctoral ThesisCollection of Articles

Abstract

Climate change and air quality are the big challenges of our time. In this work, air pollution transport to Finland, air pollution properties, their direct radiative effect on climate as well as their effect on upper tropospheric humidity are studied by using satellite data of aerosol optical properties, precipitation, clouds and upper tropospheric humidity, in situ measurement data of gases and aerosols at three measurement stations, combined with flight measurements, air mass trajectories, synoptic maps and meteorological reanalysis data. South-eastern transport routes with continental origin were found on average to bring the highest concentrations of anthropogenic gaseous and particulate pollution to southern Finland. The air masses coming from the north-east brought air that was clean of anthropogenic pollution but included high concentrations of nucleation and Aitken mode particles. Air mass trajectory statistical methods were found to be useful tools to study air pollution transport, but they were not able to reproduce emission source maps. The most severe air pollution cases in the history of air pollution measurements in Finland were produced by the biomass burning events in Eastern Europe in 2006 and 2010. The smoke was transported hundreds and even thousands of kilometres and the smoke particles were observed to grow in size during transportation. Particulate air pollution in southern Finland scattered solar radiation and had a cooling effect on climate. High absorption coefficients were measured in continental air pollution from Eastern Europe as well as in biomass burning smoke, but also these air pollutants were on average more scattering than absorbing. Based on satellite observations we were able to show the first observational evidence, with a strong emphasis on causality, that aerosols increase upper tropospheric humidity and have thus a so-far overlooked warming effect on climate. The magnitude of the observed increase is so big that the mechanism potentially has relevance for the global climate.
Original languageEnglish
Awarding Institution
  • University of Helsinki
Supervisors/Advisors
  • Kulmala, Markku, Supervisor
  • Dal Maso, Miikka, Supervisor
  • Bister, Marja, Supervisor
Award date15 Sep 2017
Place of PublicationHelsinki
Publisher
Print ISBNs978-952-7091-82-1
Electronic ISBNs978-952-7091-83-8
Publication statusPublished - 15 Sep 2017
MoE publication typeG5 Doctoral dissertation (article)

Fields of Science

  • 114 Physical sciences

Cite this

@phdthesis{9f088977bbb14e04af97db1382dd81ad,
title = "Air pollutants: Regional transport, properties and effect on upper tropospheric humidity",
abstract = "Climate change and air quality are the big challenges of our time. In this work, air pollution transport to Finland, air pollution properties, their direct radiative effect on climate as well as their effect on upper tropospheric humidity are studied by using satellite data of aerosol optical properties, precipitation, clouds and upper tropospheric humidity, in situ measurement data of gases and aerosols at three measurement stations, combined with flight measurements, air mass trajectories, synoptic maps and meteorological reanalysis data. South-eastern transport routes with continental origin were found on average to bring the highest concentrations of anthropogenic gaseous and particulate pollution to southern Finland. The air masses coming from the north-east brought air that was clean of anthropogenic pollution but included high concentrations of nucleation and Aitken mode particles. Air mass trajectory statistical methods were found to be useful tools to study air pollution transport, but they were not able to reproduce emission source maps. The most severe air pollution cases in the history of air pollution measurements in Finland were produced by the biomass burning events in Eastern Europe in 2006 and 2010. The smoke was transported hundreds and even thousands of kilometres and the smoke particles were observed to grow in size during transportation. Particulate air pollution in southern Finland scattered solar radiation and had a cooling effect on climate. High absorption coefficients were measured in continental air pollution from Eastern Europe as well as in biomass burning smoke, but also these air pollutants were on average more scattering than absorbing. Based on satellite observations we were able to show the first observational evidence, with a strong emphasis on causality, that aerosols increase upper tropospheric humidity and have thus a so-far overlooked warming effect on climate. The magnitude of the observed increase is so big that the mechanism potentially has relevance for the global climate.",
keywords = "114 Physical sciences",
author = "Riuttanen, {Laura Irmeli}",
year = "2017",
month = "9",
day = "15",
language = "English",
isbn = "978-952-7091-82-1",
series = "Report series in aerosol science",
publisher = "Finnish Association for Aerosol Research",
number = "199",
address = "Finland",
school = "University of Helsinki",

}

Air pollutants : Regional transport, properties and effect on upper tropospheric humidity. / Riuttanen, Laura Irmeli.

Helsinki : Finnish Association for Aerosol Research, 2017. 121 p.

Research output: ThesisDoctoral ThesisCollection of Articles

TY - THES

T1 - Air pollutants

T2 - Regional transport, properties and effect on upper tropospheric humidity

AU - Riuttanen, Laura Irmeli

PY - 2017/9/15

Y1 - 2017/9/15

N2 - Climate change and air quality are the big challenges of our time. In this work, air pollution transport to Finland, air pollution properties, their direct radiative effect on climate as well as their effect on upper tropospheric humidity are studied by using satellite data of aerosol optical properties, precipitation, clouds and upper tropospheric humidity, in situ measurement data of gases and aerosols at three measurement stations, combined with flight measurements, air mass trajectories, synoptic maps and meteorological reanalysis data. South-eastern transport routes with continental origin were found on average to bring the highest concentrations of anthropogenic gaseous and particulate pollution to southern Finland. The air masses coming from the north-east brought air that was clean of anthropogenic pollution but included high concentrations of nucleation and Aitken mode particles. Air mass trajectory statistical methods were found to be useful tools to study air pollution transport, but they were not able to reproduce emission source maps. The most severe air pollution cases in the history of air pollution measurements in Finland were produced by the biomass burning events in Eastern Europe in 2006 and 2010. The smoke was transported hundreds and even thousands of kilometres and the smoke particles were observed to grow in size during transportation. Particulate air pollution in southern Finland scattered solar radiation and had a cooling effect on climate. High absorption coefficients were measured in continental air pollution from Eastern Europe as well as in biomass burning smoke, but also these air pollutants were on average more scattering than absorbing. Based on satellite observations we were able to show the first observational evidence, with a strong emphasis on causality, that aerosols increase upper tropospheric humidity and have thus a so-far overlooked warming effect on climate. The magnitude of the observed increase is so big that the mechanism potentially has relevance for the global climate.

AB - Climate change and air quality are the big challenges of our time. In this work, air pollution transport to Finland, air pollution properties, their direct radiative effect on climate as well as their effect on upper tropospheric humidity are studied by using satellite data of aerosol optical properties, precipitation, clouds and upper tropospheric humidity, in situ measurement data of gases and aerosols at three measurement stations, combined with flight measurements, air mass trajectories, synoptic maps and meteorological reanalysis data. South-eastern transport routes with continental origin were found on average to bring the highest concentrations of anthropogenic gaseous and particulate pollution to southern Finland. The air masses coming from the north-east brought air that was clean of anthropogenic pollution but included high concentrations of nucleation and Aitken mode particles. Air mass trajectory statistical methods were found to be useful tools to study air pollution transport, but they were not able to reproduce emission source maps. The most severe air pollution cases in the history of air pollution measurements in Finland were produced by the biomass burning events in Eastern Europe in 2006 and 2010. The smoke was transported hundreds and even thousands of kilometres and the smoke particles were observed to grow in size during transportation. Particulate air pollution in southern Finland scattered solar radiation and had a cooling effect on climate. High absorption coefficients were measured in continental air pollution from Eastern Europe as well as in biomass burning smoke, but also these air pollutants were on average more scattering than absorbing. Based on satellite observations we were able to show the first observational evidence, with a strong emphasis on causality, that aerosols increase upper tropospheric humidity and have thus a so-far overlooked warming effect on climate. The magnitude of the observed increase is so big that the mechanism potentially has relevance for the global climate.

KW - 114 Physical sciences

M3 - Doctoral Thesis

SN - 978-952-7091-82-1

T3 - Report series in aerosol science

PB - Finnish Association for Aerosol Research

CY - Helsinki

ER -

Riuttanen LI. Air pollutants: Regional transport, properties and effect on upper tropospheric humidity. Helsinki: Finnish Association for Aerosol Research, 2017. 121 p. (Report series in aerosol science; 199).