We present a non-parametric hydro-geostatistical approach for mapping design nitrate hazard in groundwater. The approach is robust towards the uncertainty of the parametric models used to map groundwater pollution. In...We present a non-parametric hydro-geostatistical approach for mapping design nitrate hazard in groundwater. The approach is robust towards the uncertainty of the parametric models used to map groundwater pollution. In particular, probability kriging (PK) estimates the probability that the true value of a pollutant exceeds a set of threshold values using a binary response variable (probability indicator). Such soft description of the pollutant can mitigate the uncertainty in pollutant concentration mapping. PK was used for assessing nitrate migration hazard across the Campania Plain groundwater (Southern Italy) as exceeding typical critical values set to 25 and 50 mg.L-1. Cross-validation indicated that the PK is more suitable than ordinary kriging (OK), which yields large uncertainty in absolute values prediction of nitrate concentration. This means that spatial variability is critical for contaminant transport because critical contaminants concentration could be exceeded due to preferential flows allowing the pollutant to migrate rapidly through the caveats aquifer. Accordingly with PK application, about 250 km2 (40% of the total600 km2 of the Campania Plain) were classified as very sensitive areas (western zone) to maximum permissible concentration of nitrates (>50 mg.L-1). When the probability to exceed 25 mg.L-1 was considered, the contaminated surface increased to 70% of the total area.展开更多
The Silk Road Economic Belt and the 21st-Century Maritime Silk Road(B&R)aims at facilitating the twenty-first Century economic development of China.However,climate change,air quality and related feedbacks are affe...The Silk Road Economic Belt and the 21st-Century Maritime Silk Road(B&R)aims at facilitating the twenty-first Century economic development of China.However,climate change,air quality and related feedbacks are affecting the successful development of the environment and societies in the B&R geographical domain.The most urgent risks related to the atmospheric system,to the land system and to hydrospheric and cryospheric processes are changing climate-air quality interactions,air pollution,changing monsoon dynamics,land degradation,and the melting of Tibetan Plateau glaciers.A framework is needed in which a science and technology-based approach has the critical mass and expertise to identify the main steps toward solutions and is capable to implement this roadmap.The Pan-Eurasian Experiment(PEEX)program,initiated in 2012,aims to resolve science,technology and sustainability questions in the Northern Eurasian region.PEEX is now identifying its science agenda for the B&R region.One fundamental element of the PEEX research agenda is the availability of comprehensive ground-based observations together with Earth observation data.PEEX complements the recently launched international scientific program called Digital Belt and Road(DBAR).PEEX has expertise to coordinate the ground-based observations and initiate new flagship stations,while DBAR provides a big data platform on Earth observation from China and countries along the Belt and Road region.The DBAR and PEEX have joint interests and synergy expertise on monitoring on ecological environment,urbanization,cultural heritages,coastal zones,and arctic cold regions supporting the sustainable development of the Belt and Road region.In this paper we identify the research themes of the PEEX related Silk Road agenda relevant to China and give an overview of the methodological requirements and present the infrastructure requirements needed to carry out large scale research program.展开更多
It has been suggested that forest fires will become more frequent/intense with changing climate,which would increase aerosol/gas emissions into the atmosphere.A better under-standing of the relations between meteorolo...It has been suggested that forest fires will become more frequent/intense with changing climate,which would increase aerosol/gas emissions into the atmosphere.A better under-standing of the relations between meteorological conditions,fires,and fire emissions will help estimate the climate response via forest fires.In this study,we use ERA5 meteor-ological products,including temperature,precipitation,and soil moisture,to explain the frequency of forest fires and the amount of radiant energy released per time unit by burning vegetation(fire radiative power,FRP).We explore the relation-ships between satellite-retrieved fire products and aerosol properties(aerosol optical depth,AOD),carbon monoxide(CO),formaldehyde(HCHO),and nitrogen dioxide(NO_(2))con-centrations over the PEEX domain,which covers different vegetation zones(e.g.croplands/grasslands,forest,arctic tun-dra)of Pan-Eurasia and China.We analyse the concentrations of black carbon and absorbing organic carbon using groundbased AErosol RObotic NETwork.The analysis covers the months of May to August from 2002 to 2022.We show posi-tive temperature trends in the Northern zone(>65°N)in June and August(1.56°C and 0.64°C,respectively);all statistically significant trends for precipitation and soil moisture are nega-tive.This can explain increased fire activity in Siberia over the recent years(2019-2022).Over the whole PEEX domain,FC and FRP trends remain insignificant or negative;a decrease in AOD may address those negative trends.We show that intrasummer variations exist for cropland/grassland fires,which occur most often in May and August,while Siberian forest fires occur more often in July and August.We show that CO concentration has been gradually decreasing in the last two decades in May and June.CO trends are negative in May,June,and over summer for all regions,in July in Europe,China,the Southern zone(<55°N),and the PEEX domain.HCHO trends are not significant in all regions.NO_(2)trends are positive in May and negative in June in all zones.We calculated total column enhancement ratios for satellite obser-vations influenced by wildfires.A common feature has been recognized with measurements and ratios utilized in SILAM(System for Integrated Modelling of Atmospheric Composition):AOD(or PM):CO and AOD(or PM):HCHO ratios for grass are clearly lower than for shrubs,opposite for AOD:NO_(2).We showed that emission ratios are increasing towards South and are 2-3 times higher for high(>0.5)AOD.Using a 21-year satellite record of the AOD and CO,an 18-year record of NO_(2),and a 16-year record of HCHO,we created background products of those variables over the PEEX domain.In the regions with low anthropogenic activity and conditions where long-range transport is not happening,anomalies in AOD,CO,and HCHO over biomass-burning areas may be assigned directly to the wildfire emissions.展开更多
文摘We present a non-parametric hydro-geostatistical approach for mapping design nitrate hazard in groundwater. The approach is robust towards the uncertainty of the parametric models used to map groundwater pollution. In particular, probability kriging (PK) estimates the probability that the true value of a pollutant exceeds a set of threshold values using a binary response variable (probability indicator). Such soft description of the pollutant can mitigate the uncertainty in pollutant concentration mapping. PK was used for assessing nitrate migration hazard across the Campania Plain groundwater (Southern Italy) as exceeding typical critical values set to 25 and 50 mg.L-1. Cross-validation indicated that the PK is more suitable than ordinary kriging (OK), which yields large uncertainty in absolute values prediction of nitrate concentration. This means that spatial variability is critical for contaminant transport because critical contaminants concentration could be exceeded due to preferential flows allowing the pollutant to migrate rapidly through the caveats aquifer. Accordingly with PK application, about 250 km2 (40% of the total600 km2 of the Campania Plain) were classified as very sensitive areas (western zone) to maximum permissible concentration of nitrates (>50 mg.L-1). When the probability to exceed 25 mg.L-1 was considered, the contaminated surface increased to 70% of the total area.
基金This work was support from the Academy of Finland Center of Excellence[grant number 307331]the Academy of Finland Academy Professor[grant number 307567],ERC Advanced grant[project ID 742206],Digital Belt&Road of CAS Strategic Priority Research Program[grant number XDA19030402]the Academy of Finland projects ABBA No.280700(2014-2017)and ClimEco No.314798/799(2018-2020)and Russian Science Foundation projects No.15-17-20009(2015-2018)and No.15-17-30009(2015-2018).
文摘The Silk Road Economic Belt and the 21st-Century Maritime Silk Road(B&R)aims at facilitating the twenty-first Century economic development of China.However,climate change,air quality and related feedbacks are affecting the successful development of the environment and societies in the B&R geographical domain.The most urgent risks related to the atmospheric system,to the land system and to hydrospheric and cryospheric processes are changing climate-air quality interactions,air pollution,changing monsoon dynamics,land degradation,and the melting of Tibetan Plateau glaciers.A framework is needed in which a science and technology-based approach has the critical mass and expertise to identify the main steps toward solutions and is capable to implement this roadmap.The Pan-Eurasian Experiment(PEEX)program,initiated in 2012,aims to resolve science,technology and sustainability questions in the Northern Eurasian region.PEEX is now identifying its science agenda for the B&R region.One fundamental element of the PEEX research agenda is the availability of comprehensive ground-based observations together with Earth observation data.PEEX complements the recently launched international scientific program called Digital Belt and Road(DBAR).PEEX has expertise to coordinate the ground-based observations and initiate new flagship stations,while DBAR provides a big data platform on Earth observation from China and countries along the Belt and Road region.The DBAR and PEEX have joint interests and synergy expertise on monitoring on ecological environment,urbanization,cultural heritages,coastal zones,and arctic cold regions supporting the sustainable development of the Belt and Road region.In this paper we identify the research themes of the PEEX related Silk Road agenda relevant to China and give an overview of the methodological requirements and present the infrastructure requirements needed to carry out large scale research program.
基金This study is realised within the frameworks of the PEEX Programme Science Plan as well as with financial support from the Academy of Finland grant No 337549(Atmosphere and Climate Competence Centre,ACCC).
文摘It has been suggested that forest fires will become more frequent/intense with changing climate,which would increase aerosol/gas emissions into the atmosphere.A better under-standing of the relations between meteorological conditions,fires,and fire emissions will help estimate the climate response via forest fires.In this study,we use ERA5 meteor-ological products,including temperature,precipitation,and soil moisture,to explain the frequency of forest fires and the amount of radiant energy released per time unit by burning vegetation(fire radiative power,FRP).We explore the relation-ships between satellite-retrieved fire products and aerosol properties(aerosol optical depth,AOD),carbon monoxide(CO),formaldehyde(HCHO),and nitrogen dioxide(NO_(2))con-centrations over the PEEX domain,which covers different vegetation zones(e.g.croplands/grasslands,forest,arctic tun-dra)of Pan-Eurasia and China.We analyse the concentrations of black carbon and absorbing organic carbon using groundbased AErosol RObotic NETwork.The analysis covers the months of May to August from 2002 to 2022.We show posi-tive temperature trends in the Northern zone(>65°N)in June and August(1.56°C and 0.64°C,respectively);all statistically significant trends for precipitation and soil moisture are nega-tive.This can explain increased fire activity in Siberia over the recent years(2019-2022).Over the whole PEEX domain,FC and FRP trends remain insignificant or negative;a decrease in AOD may address those negative trends.We show that intrasummer variations exist for cropland/grassland fires,which occur most often in May and August,while Siberian forest fires occur more often in July and August.We show that CO concentration has been gradually decreasing in the last two decades in May and June.CO trends are negative in May,June,and over summer for all regions,in July in Europe,China,the Southern zone(<55°N),and the PEEX domain.HCHO trends are not significant in all regions.NO_(2)trends are positive in May and negative in June in all zones.We calculated total column enhancement ratios for satellite obser-vations influenced by wildfires.A common feature has been recognized with measurements and ratios utilized in SILAM(System for Integrated Modelling of Atmospheric Composition):AOD(or PM):CO and AOD(or PM):HCHO ratios for grass are clearly lower than for shrubs,opposite for AOD:NO_(2).We showed that emission ratios are increasing towards South and are 2-3 times higher for high(>0.5)AOD.Using a 21-year satellite record of the AOD and CO,an 18-year record of NO_(2),and a 16-year record of HCHO,we created background products of those variables over the PEEX domain.In the regions with low anthropogenic activity and conditions where long-range transport is not happening,anomalies in AOD,CO,and HCHO over biomass-burning areas may be assigned directly to the wildfire emissions.
