7 research outputs found
Simple proxy for continental concentration of accumulation mode particles using reanalysis data
Cloud condensation nuclei (CCN) participate in controlling the climate, and a better understading of their number concentrations is needed to constrain the current uncertainties in Earth’s energy budget. However, estimating the global CCN concentrations is difficult using only localised in-situ measurements. To overcome this, different proxies and parametrisations for CCN have been developed. In this thesis, accumulation mode particles were used as a substitute for CCN, and continental proxy for number concentration of N100 was developed with CO and temperature as tracers for anthropogenic and biogenic emissions. The data utilised in the analysis contained N100 measurements from 22 sites from 5 different continents as well as CO and temperature from CAMS reanalysis dataset.
The thesis aimed to construct a global continental proxy. In addition to this, individual proxies for each site (the site proxy) and proxies trained with other sites’ data (the site excluded proxy) were developed. The performance of these proxies was evaluated using a modified version of K-fold cross-validation, which allowed estimating the effect of dataset selection on the results. Additionally, time series, seasonal variation, and parameter distributions for developed proxies were analysed and findings compared against known characteristics of the sites.
Global proxy was developed, but no single set of parameters, that would achieve the best performance at all sites, was found. Therefore, two versions of global proxy were selected and their results analysed. For most of the sites, the site proxy performed better than the global proxies. Additionally, based on the analysis from the site excluded proxy, extrapolating the global proxy to new locations produced results with varying accuracy. Best results came from sites with low concentrations and occasional anthropogenic transport episodes. Additionally, some European rural sites performed well, whereas in mountainous sites the proxy struggled. Comparing the proxy to literature, it performed generally less well or similarly as proxies from other studies. Longer datasets and additional measurement sites could improve the proxy performance
Opinion: Insights into updating Ambient Air Quality Directive 2008/50/EC
As evidence of adverse health effects due to air pollution continues to increase, the World Health Organization (WHO) recently published its latest edition of the global air quality guidelines (World Health Organization, 2021). Although not legally binding, the guidelines aim to provide a framework in which policymakers can combat air pollution by formulating evidence-based air quality management strategies. In the light of this, the European Union has stated its intent to revise the current ambient air quality directive (2008/50/EC) to more closely resemble the newly published WHO guidelines (European Commission, 2020). This article provides an informed opinion on selected features of the air quality directive that we believe would benefit from a reassessment. The selected features include discussion about (1) air quality sensors as a part of a hierarchical observation network, (2) the number of minimum sampling points and their siting criteria, and (3) new target air pollution parameters for future consideration.Peer reviewe
Added Value of Vaisala AQT530 Sensors as a Part of a Sensor Network for Comprehensive Air Quality Monitoring
Poor air quality influences the quality of life in the urban environment. The regulatory observation stations provide the backbone for the city administration to monitor urban air quality. Recently a suite of cost-effective air quality sensors has emerged to provide novel insights into the spatio-temporal variability of aerosol particles and trace gases. Particularly in low concentrations these sensors might suffer from issues related e.g., to high detection limits, concentration drifts and interdependency between the observed trace gases and environmental parameters. In this study we characterize the optical particle detector used in AQT530 (Vaisala Ltd.) air quality sensor in the laboratory. We perform a measurement campaign with a network of AQT530 sensors in Helsinki, Finland in 2020-2021 and present a long-term performance evaluation of five sensors for particulate (PM10, PM2.5) and gaseous (NO2, NO, CO, O-3) components during a half-year co-location study with reference instruments at an urban traffic site. Furthermore, short-term (3-5 weeks) co-location tests were performed for 25 sensors to provide sensor-specific correction equations for the fine-tuning of selected pollutants in the sensor network. We showcase the added value of the verified network of 25 sensor units to address the spatial variability of trace gases and aerosol mass concentrations in an urban environment. The analysis assesses road and harbor traffic monitoring, local construction dust monitoring, aerosol concentrations from fireworks, impact of sub-urban small scale wood combustion and detection of long-range transport episodes on a city scale. Our analysis illustrates that the calibrated network of Vaisala AQT530 air quality sensors provide new insights into the spatio-temporal variability of air pollution within the city. This information is beneficial to, for example, optimization of road dust and construction dust emission control as well as provides data to tackle air quality problems arising from traffic exhaust and localized wood combustion emissions in the residential areas.Peer reviewe
Overview : Integrative and Comprehensive Understanding on Polar Environments (iCUPE) - concept and initial results
The role of polar regions is increasing in terms of megatrends such as globalization, new transport routes, demography, and the use of natural resources with consequent effects on regional and transported pollutant concentrations. We set up the ERA-PLANET Strand 4 project "iCUPE - integrative and Comprehensive Understanding on Polar Environments" to provide novel insights and observational data on global grand challenges with an Arctic focus. We utilize an integrated approach combining in situ observations, satellite remote sensing Earth observations (EOs), and multi-scale modeling to synthesize data from comprehensive long-term measurements, intensive campaigns, and satellites to deliver data products, metrics, and indicators to stakeholders concerning the environmental status, availability, and extraction of natural resources in the polar areas. The iCUPE work consists of thematic state-of-the-art research and the provision of novel data in atmospheric pollution, local sources and transboundary transport, the characterization of arctic surfaces and their changes, an assessment of the concentrations and impacts of heavy metals and persistent organic pollutants and their cycling, the quantification of emissions from natural resource extraction, and the validation and optimization of satellite Earth observation (EO) data streams. In this paper we introduce the iCUPE project and summarize initial results arising out of the integration of comprehensive in situ observations, satellite remote sensing, and multi-scale modeling in the Arctic context.Peer reviewe
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Overview: Integrative and Comprehensive Understanding on Polar Environments (iCUPE) – concept and initial results
The role of polar regions is increasing in terms of megatrends such as globalization, new transport routes, demography, and the use of natural resources with consequent effects on regional and transported pollutant concentrations. We set up the ERA-PLANET Strand 4 project “iCUPE – integrative and Comprehensive Understanding on Polar Environments” to provide novel insights and observational data on global grand challenges with an Arctic focus. We utilize an integrated approach combining in situ observations, satellite remote sensing Earth observations (EOs), and multi-scale modeling to synthesize data from comprehensive long-term measurements, intensive campaigns, and satellites to deliver data products, metrics, and indicators to stakeholders concerning the environmental status, availability, and extraction of natural resources in the polar areas. The iCUPE work consists of thematic state-of-the-art research and the provision of novel data in atmospheric pollution, local sources and transboundary transport, the characterization of arctic surfaces and their changes, an assessment of the concentrations and impacts of heavy metals and persistent organic pollutants and their cycling, the quantification of emissions from natural resource extraction, and the validation and optimization of satellite Earth observation (EO) data streams. In this paper we introduce the iCUPE project and summarize initial results arising out of the integration of comprehensive in situ observations, satellite remote sensing, and multi-scale modeling in the Arctic context
Apua - Minustako auttaja? : ensiavun opettaminen lukion ensimmäiselle vuosikurssille
Tämä opinnäytetyö on toiminnallinen projekti. Projektin aiheeksi valittiin ensiavun opettaminen nuorille, koska tilastoja tarkasteltaessa nuoret olivat alttiimpia onnettomuuksille ja tapaturmille verrattaessa iältään vanhempaan väestöön (Hai-konen 2010, 16). Ensiapua haluttiin opettaa juuri nuorille, koska tutkimusten mukaan heillä on huomattavasti alhaisempi turvallisuustietous kuin esimerkiksi 25–30-vuotiailla (Palukka 2006).
Projektin tavoitteena oli järjestää ensiapukoulutus Lahden Lyseon lukion ensimmäisen vuosikurssin oppilaista kootulle oppilasryhmälle syksyllä 2011. Tavoitteena oli opettaa nuorille keskeisiä ensiaputaitoja, herättää nuorten kiinnostusta omia ensiapuvalmiuksia kohtaan, kehittää ensiaputilanteissa tarvittavia taitoja, sekä lisätä rohkeutta toimia ensiaputilanteissa. Pitkäaikaisena tavoitteena oli myös terveyden ja hyvinvoinnin edistäminen sekä vaikuttaminen nuorten liikennekäyttäytymiseen positiivisesti.
Projektin tavoitteiden kannalta oli tärkeää selvittää ensiaputilanteisiin joutumisen yleisyys sekä lisäopetuksen tarve. Tämä selvitettiin alkukartoituksen (LIITE 1) avulla. Opetussisältö koottiin SPR:n ensiapuoppaasta, alkukartoituksen vastauksista ja tapaturmatilastoista. Alkukartoitus toteutettiin koko Lahden lyseon lukion opiskelijoiden kesken, ja vastaajia oli yhteensä 185.
Ensiapukoulutuksen järjestämiseen saatiin aikaa viiden opetustunnin verran (á 75 min). Ensiapuopetusryhmään osallistui vapaaehtoisesti 11 opiskelijaa. Tunnit pidettiin pääasiassa liikuntatuntien aikana. Opetuksessa hyödynnettiin monipuolisesti erilaisia opetusmenetelmiä, kuten teoriaa ja käytännön harjoituksia.
Tavoitteiden saavuttamista arvioitiin palautelomakkeella (LIITE 11) sekä opiskelijoiden ensiaputaitoja kartoittavalla kyselyllä (LIITE 10). Kyselyyn vastattiin ennen ja jälkeen koulutuksen. Oikeinvastausprosentti oli huomattavasti suurempi koulutuksen jälkeen. Opiskelijat antoivat kirjallisesti palautetta projektin onnistumisesta. Positiivisen palautteen ja kyselyn perusteella voitiin päätellä projektin tavoitteiden täyttyneen.This Bachelor’s Thesis is an implementation of the project. Teaching first-aid skills for young people was chosen to be the subject of the project because they are more likely to get involved in accidents when comparing them to elderly people. First aid was specifically wanted to teach to young people because, according to a research (Palukka 2006), they have considerably lower knowledge of safety compared to young adults aged 25-30.
The goal was to organize first-aid training to a group of first year students from Lahden lyseon lukio at autumn 2011. The target was to teach them essential skills of first-aid, to arouse young peoples’ interest towards their own first-aid preparedness, to develope skills that you need in emergency situations and to add courage to act in emergency situations. The long term goal was to promote health and well-being and to influence positively to young peoples’ traffic behavior.
It was important to resolve how common it is to end up in an emergency situation, and is there any need for further education. This information was gathered from a survey (ATTACHMENT 1). The educational content was gathered from first-aid guide (SPR), from a survey and from accident statistics. The survey was executed among all students in Lahden lyseon lukio and there were 185 respondents.
The time that was given to arrange the first-aid training was five lessons (á 75 min). There were 11 voluntiers to participate for the first-aid training group. The training took mainly place while sport lessons. There were versatile teaching methods used during the training for example theory and practical training.
Feedback forms (ATTACHMENT 11) and the query, (ATTACHMENT 10) which was made to resolve students´ first-aid skills were used to evaluate how the goals of the project were gained. The query was answered before the education and after it. There were significantly more correct answers after the training. According to the positive feedback and the query the goals of the project were achieved
Measurement report : The 4-year variability and influence of the Winter Olympics and other special events on air quality in urban Beijing during wintertime
Comprehensive measurements are vital to obtain big enough datasets for better understanding the complex atmosphere and further improving the air quality. To investigate the 4-year variation of air quality and the influences of special events (Beijing Winter Olympics, COVID lockdown and Chinese New Year) on it during the wintertime in polluted urban air, we conducted comprehensive observations in Beijing, China, during 1 January-20 February, in the years from 2019 to 2022. The mass concentration of PM2 :5 and its composition (organics, nitrate, sulfate, ammonium, chloride and black carbon) and the number size distributions of particles (down to similar to 1 nm) and ions, gaseous pollutants (CO, NO x, SO2, O-3) and condensable vapors (sulfuric acid and oxygenated organic molecules), as well as meteorological parameters, were simultaneously measured. The days before 22 January without any special events in each year were selected to investigate the 4-year variability of air quality. We found that the concentrations of CO, NO x, total oxygenated organic molecules (OOMs), total PM2 :5, organics, chloride and black carbon and the number concentration of sub-3 nm particles ( N1 :3 3) showed similar variations, decreasing from 2019 to 2021 and then increasing in 2022. For SO2, however, its concentration decreased year by year due to the significant emission reduction, further leading to the decrease of gaseous sulfuric acid and particulate sulfate from 2019 to 2022. O-3 concentration showed an opposite 4-year variation compared with NO x. Meanwhile, both the oxygen and nitrogen contents of oxygenated organic molecules increased year by year, implying that not only the oxidation state of those compounds increased, but also NO x was involved more efficiently in their formation processes. With higher sulfuric acid concentrations and new particle formation (NPF) frequencies in 2021 than in 2022, and with the lowest concentrations of background aerosols and the lowest ambient temperatures in 2021, N1 :3 3 was still the lowest in 2021. Unlike N1 :3 3, the ion concentrations in both 0.8-2 and 2-4 nm size ranges were higher in 2021 than in the other years. Then, the days after 4 February were chosen to explore the influence of special events. The non-event days within this date range in 2019 and 2021 were chosen as the reference period. Due to the favorable meteorological conditions together with reductions in anthropogenic emissions, there were basically no haze events during the Olympics. Therefore, CO, NO x, SO2(,) total OOMs, accumulation-mode particles ( N100 1000), and total PM2 :5 and its composition were much lower, while ion concentrations were much higher compared with the reference period. Although there was also emission reduction during COVID, especially for NO x, the enhancement of secondary inorganic aerosol formation, together with unfavorable meteorological conditions, caused severe haze events during this period. Hence, CO, total OOMs and all PM2 :5 compositions during COVID increased dramatically compared with the reference period. Influenced by SO2, condensation sink and sunlight, sulfuric acid concentration was found to be comparable between the Olympics and the reference period but was lower during COVID and Chinese New Year. Additionally, N1 :3 3 was almost at the same level during different periods, indicating that the special events only had little impact on the NPF processes. These results provide useful information to the development of more targeted pollution control plans.Peer reviewe