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IOP Publishing
2023
2009
2019
Active vegetation fires in south-eastern (SE) Europe resulted in a notable increase in the number concentration of aerosols and cloud condensation nuclei (CCN) particles at two high latitude locations—the SMEAR IV station in Kuopio, Finland, and the Zeppelin Observatory in Svalbard, high Arctic. During the fire episode aerosol hygroscopicity κ slightly increased at SMEAR IV and at the Zeppelin Observatory κ decreased. Despite increased κ in high CCN conditions at SMEAR IV, the aerosol activation diameter increased due to the decreased supersaturation with an increase in aerosol loading. In addition, at SMEAR IV during the fire episode, in situ measured cloud droplet number concentration (CDNC) increased by a factor of ∼7 as compared to non-fire periods which was in good agreement with the satellite observations (MODIS, Terra). Results from this study show the importance of SE European fires for cloud properties and radiative forcing in high latitudes.
American Geophysical Union (AGU)
2024
2010
2010
2010
2001
2013
Ny-Ålesund is an international research settlement where the thermodynamics and chemical composition of the air are monitored. The present work investigates the effects of micrometeorological conditions, mesoscale dynamics and local air pollution on the data collected at two different locations around the village. Daily filter measurements of sulphur dioxide and non-sea salt sulphate from the temporary Ny-Ålesund station and permanent Zeppelin mountain station have been analysed along with meteorological data. The influence of different factors representing micrometeorological phenomena and local pollution from ships has been statistically investigated. Seasonal variation of the correlation between the data from Ny-Ålesund and Zeppelin stations is revealed, and the seasonal dependence of the relative contribution of different factors has been analysed. The median concentrations of SO42- measured in Ny-Ålesund increased significantly on days with temperature inversions in winter. In spring, concentrations of SO2 and SO42- were higher than normal at both stations on days with temperature inversions, but lower on days with strong humidity inversions. In summer, local ship traffic affects the SO2 data set from Ny-Ålesund, while no statistically significant influence on the Zeppelin data set has been observed. The pollution from ships has an effect on SO42- values at both stations; however, the concentrations in Ny-Ålesund were higher when local pollution accumulated close to the ground in days with strong humidity inversions.
2018
2015
2024
2006
2016
2007
2012
Effects of climate variability on vegetation and carbon uptake in a North-Norwegian coastal wetland. NILU OR
Drivhusgassutveksling mellom terrestre økosystemer og atmosfæren er et viktig element i klimasystemet, og utslipp fra boreale og polare våtmarksområder er muligens avgjørende for den videre utviklingen av atmosfæriske konsentrasjoner av CO2 og metan, fordi de inneholder like mye av disse gassene som atmosfæren i dag. Målet med dette prosjektet var å estimere flukser av CO2 og metan i en nordnorsk kystmyr. Sju år med observasjoner viser at disse er sammenlignbare med verdier fra kystmyr ved lavere breddegrader og klart forskjellige fra alpine og mer kontinentale myr i Nord-Sverige og Nord-Finland. Den også sju år lange serien av meteorologiske data dokumenterer at været i denne perioden var både signifikant varmere (hele året, men spesielt om vinteren) og tørrere (spesielt om sommeren) enn normalen fra perioden 1961-1990. Karbonflukser i vekstperioden er følsomme for både tørke, kulde og forholdene i jordsmonnet før vekstperioden, men netto-økosystem-utvekslingen for et helt år varierer langt mindre.
2015
The effect of the 2018 extreme meteorological conditions in Europe on methane (CH4) emissions is examined using estimates from four atmospheric inversions calculated for the period 2005–2018. For most of Europe, we find no anomaly in 2018 compared to the 2005–2018 mean. However, we find a positive anomaly for the Netherlands in April, which coincided with positive temperature and soil moisture anomalies suggesting an increase in biogenic sources. We also find a negative anomaly for the Netherlands for September–October, which coincided with a negative anomaly in soil moisture, suggesting a decrease in soil sources. In addition, we find a positive anomaly for Serbia in spring, summer and autumn, which coincided with increases in temperature and soil moisture, again suggestive of changes in biogenic sources, and the annual emission for 2018 was 33 ± 38% higher than the 2005–2017 mean. These results indicate that CH4 emissions from areas where the natural source is thought to be relatively small can still vary due to meteorological conditions. At the European scale though, the degree of variability over 2005–2018 was small, and there was negligible impact on the annual CH4 emissions in 2018 despite the extreme meteorological conditions.
This article is part of a discussion meeting issue ‘Rising methane: is warming feeding warming? (part 2)’.
2021
2019
2019
2009