Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Antti-Ilari Partanen is active.

Publication


Featured researches published by Antti-Ilari Partanen.


Journal of Geophysical Research | 2012

Direct and indirect effects of sea spray geoengineering and the role of injected particle size

Antti-Ilari Partanen; H. Kokkola; S. Romakkaniemi; Veli-Matti Kerminen; K. E. J. Lehtinen; T. Bergman; Antti Arola; Hannele Korhonen

[1] Climate-aerosol model ECHAM5.5-HAM2 was used to investigate how geoengineering with artificial sea salt emissions would affect marine clouds and the Earth’s radiative balance. Prognostic cloud droplet number concentration and interaction of aerosol particles with clouds and radiation were calculated explicitly, thus making this the first time that aerosol direct effects of sea spray geoengineering are considered. When a wind speed dependent baseline geoengineering flux was applied over all oceans (total annual emissions 443.9 Tg), we predicted a radiative flux perturbation (RFP) of 5.1 W m , which is enough to counteract warming from doubled CO2 concentration. When the baseline flux was limited to three persistent stratocumulus regions (3.3% of Earth’s surface, total annual emissions 20.6 Tg), the RFP was 0.8 Wm 2 resulting mainly from a 74–80% increase in cloud droplet number concentration and a 2.5–4.4 percentage point increase in cloud cover. Multiplying the baseline mass flux by 5 or reducing the injected particle size from 250 to 100 nm had comparable effects on the geoengineering efficiency with RFPs 2.2 and 2.1 Wm , respectively. Within regions characterized with persistent stratocumulus decks, practically all of the radiative effect originated from aerosol indirect effects. However, when all oceanic regions were seeded, the direct effect with the baseline flux was globally about 29% of the total radiative effect. Together with previous studies, our results indicate that there are still large uncertainties associated with the sea spray geoengineering efficiency due to variations in e.g., background aerosol concentration, updraft velocity, cloud altitude and onset of precipitation.


Geophysical Research Letters | 2014

Climate impacts of changing aerosol emissions since 1996

Thomas Kühn; Antti-Ilari Partanen; Anton Laakso; Zifeng Lu; T. Bergman; Santtu Mikkonen; H. Kokkola; Hannele Korhonen; P. Räisänen; David G. Streets; S. Romakkaniemi; Ari Laaksonen

Increases in Asian aerosol emissions have been suggested as one possible reason for the hiatus in global temperature increase during the past 15 years. We study the effect of sulphur and black carbon (BC) emission changes between 1996 and 2010 on the global energy balance. We find that the increased Asian emissions have had very little regional or global effects, while the emission reductions in Europe and the U.S. have caused a positive radiative forcing. In our simulations, the global-mean aerosol direct radiative effect changes by 0.06 W/m2 during 1996 to 2010, while the effective radiative forcing (ERF) is 0.42 W/m2. The rather large ERF arises mainly from changes in cloudiness, especially in Europe. In Asia, the BC warming due to sunlight absorption has largely offset the cooling caused by sulphate aerosols. Asian BC concentrations have increased by a nearly constant fraction at all altitudes, and thus, they warm the atmosphere also in cloudy conditions.


Environmental Research Letters | 2012

Stratospheric passenger flights are likely an inefficient geoengineering strategy

Anton Laakso; Antti-Ilari Partanen; H. Kokkola; Ari Laaksonen; K. E. J. Lehtinen; Hannele Korhonen

Solar radiation management with stratospheric sulfur aerosols has been proposed as a potential geoengineering strategy to reduce global warming. However, there has been very little investigation on the efficiency of specific injection methods suggested. Here, we show that using stratospheric passenger flights to inject sulfate aerosols would not cause significant forcing under realistic injection scenarios: even if all present-day intercontinental flights were lifted above the tropopause, we simulate global surface shortwave radiative forcings of 0:05 W m 2 and 0:10 W m 2 with current and five times enhanced fuel sulfur concentrations, respectively. In the highly unlikely scenario that fuel sulfur content is enhanced by a factor of 50 (i.e. ten times the current legal limit) the radiative forcing is 0:85 W m 2 . This is significantly lower than if the same amount of sulfur were injected over the tropics ( 1:32 W m 2 , for 3 Tg (S) yr 1 ) due to a faster loss rate and lower intensity of solar radiation in the northern midlatitudes where current flight paths are concentrated. We also predict lower global forcing in northern hemisphere winter than in summer due to the seasonalities of the solar radiation intensity at midlatitudes, the related OH chemistry that produces sulfate aerosol, and removal of particles.


Geophysical Research Letters | 2016

Impacts of sea spray geoengineering on ocean biogeochemistry

Antti-Ilari Partanen; David P. Keller; Hannele Korhonen; H. Damon Matthews

We used an earth system model of intermediate complexity to study the effects of Solar Radiation Management (SRM) by sea spray geoengineering on ocean biogeochemistry. SRM slightly decreased global ocean net primary productivity (NPP) relative to the control run. The lower temperatures in the SRM run decreased NPP directly but also indirectly increased NPP in some regions due to changes in nutrient availability resulting from changes in ocean stratification and circulation. Reduced light availability had a minor effect on global total NPP but a major regional effect near the nutrient rich upwelling region off the coast of Peru, where light availability is the main limiting factor for phytoplankton growth in our model. Unused nutrients from regions with decreased NPP also fueled NPP elsewhere. In the context of RCP4.5 simulation used here, SRM decreased ocean carbon uptake due to changes in atmospheric CO2 concentrations, seawater chemistry, NPP, temperature, and ocean circulation.


Scientific Reports | 2018

1.5 °C carbon budget dependent on carbon cycle uncertainty and future non-CO 2 forcing

Nadine Mengis; Antti-Ilari Partanen; Jonathan Jalbert; H. Damon Matthews

Estimates of the 1.5 °C carbon budget vary widely among recent studies, emphasizing the need to better understand and quantify key sources of uncertainty. Here we quantify the impact of carbon cycle uncertainty and non-CO2 forcing on the 1.5 °C carbon budget in the context of a prescribed 1.5 °C temperature stabilization scenario. We use Bayes theorem to weight members of a perturbed parameter ensemble with varying land and ocean carbon uptake, to derive an estimate for the fossil fuel (FF) carbon budget of 469 PgC since 1850, with a 95% likelihood range of (411,528) PgC. CO2 emissions from land-use change (LUC) add about 230 PgC. Our best estimate of the total (FF + LUC) carbon budget for 1.5 °C is therefore 699 PgC, which corresponds to about 11 years of current emissions. Non-CO2 greenhouse gas and aerosol emissions represent equivalent cumulative CO2 emissions of about 510 PgC and −180 PgC for 1.5 °C, respectively. The increased LUC, high non-CO2 emissions and decreased aerosols in our scenario, cause the long-term FF carbon budget to decrease following temperature stabilization. In this scenario, negative emissions would be required to compensate not only for the increasing non-CO2 climate forcing, but also for the declining natural carbon sinks.


Journal of Geophysical Research | 2015

From nuclear power to coal power: Aerosol induced health and radiative effects

T. Mielonen; Anton Laakso; Anni Karhunen; H. Kokkola; Antti-Ilari Partanen; Hannele Korhonen; Sami Romakkaniemi; K. E. J. Lehtinen

We have investigated what would be the climate and PM-induced air quality consequences if all nuclear reactors worldwide were closed down and replaced by coal combustion. In a way, this presents a “worst-case scenario” since less polluting energy sources are available. We studied simultaneously the radiative and health effects of coal power emissions using a global 3-D aerosol-climate model (ECHAM-HAMMOZ). This approach allowed us to estimate the effects of a major global energy production change from low carbon source to a high carbon one using detailed spatially resolved population density information. We included the radiative effects of both CO2 and PM2.5 but limited the study of health effects to PM2.5 only. Our results show that the replacement of nuclear power with coal power would have globally caused an average of 150,000 premature deaths per year during the period 2005–2009 with two thirds of them in Europe. For 37 years the aerosol emissions from the additional coal power plants would cool the climate but after that the accumulating CO2 emissions would accelerate the warming of the climate.


Journal of Geophysical Research | 2013

Sea spray geoengineering experiments in the geoengineering model intercomparison project (GeoMIP): Experimental design and preliminary results

Ben Kravitz; Piers M. Forster; Andy Jones; Alan Robock; Kari Alterskjær; Olivier Boucher; A. K. L. Jenkins; Hannele Korhonen; Jón Egill Kristjánsson; Helene Muri; Ulrike Niemeier; Antti-Ilari Partanen; Philip J. Rasch; Hailong Wang; Shingo Watanabe


Geophysical Research Letters | 2012

Surfactant effects in global simulations of cloud droplet activation

N. L. Prisle; Ari Asmi; David Topping; Antti-Ilari Partanen; S. Romakkaniemi; M. Dal Maso; Markku Kulmala; Ari Laaksonen; K. E. J. Lehtinen; Gordon McFiggans; H. Kokkola


Atmospheric Chemistry and Physics | 2013

Climate and air quality trade-offs in altering ship fuel sulfur content

Antti-Ilari Partanen; Anton Laakso; Anja Schmidt; H. Kokkola; T. Kuokkanen; J.-P. Pietikäinen; V.-M. Kerminen; K. E. J. Lehtinen; Lauri Laakso; Hannele Korhonen


Atmospheric Chemistry and Physics | 2016

Radiative and climate impacts of a large volcanic eruption during stratospheric sulfur geoengineering

Anton Laakso; H. Kokkola; Antti-Ilari Partanen; Ulrike Niemeier; Claudia Timmreck; K. E. J. Lehtinen; H. Hakkarainen; Hannele Korhonen

Collaboration


Dive into the Antti-Ilari Partanen's collaboration.

Top Co-Authors

Avatar

Hannele Korhonen

Finnish Meteorological Institute

View shared research outputs
Top Co-Authors

Avatar

H. Kokkola

Finnish Meteorological Institute

View shared research outputs
Top Co-Authors

Avatar

K. E. J. Lehtinen

University of Eastern Finland

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Anton Laakso

Finnish Meteorological Institute

View shared research outputs
Top Co-Authors

Avatar

Ari Laaksonen

Finnish Meteorological Institute

View shared research outputs
Top Co-Authors

Avatar

S. Romakkaniemi

University of Eastern Finland

View shared research outputs
Top Co-Authors

Avatar

T. Bergman

Finnish Meteorological Institute

View shared research outputs
Top Co-Authors

Avatar

Antti Arola

Finnish Meteorological Institute

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge