{"id":8205,"date":"2026-08-22T18:35:06","date_gmt":"2026-08-22T16:35:06","guid":{"rendered":"https:\/\/ustarch.sav.sk\/sk\/aerosol-properties-bratislava-21-august-2026\/"},"modified":"2026-09-23T09:11:15","modified_gmt":"2026-09-23T07:11:15","slug":"aerosol-properties-bratislava-21-august-2026","status":"publish","type":"post","link":"https:\/\/ustarch.sav.sk\/sk\/aerosol-properties-bratislava-21-august-2026\/","title":{"rendered":"Our research also requires knowledge of aerosol parameters \u2013 current data for Bratislava"},"content":{"rendered":"
\n
COPERNICUS CAMS \u00b7 AEROSOL PARAMETERS<\/div>\n

Aerosols are an important part of the optical state of the atmosphere because they influence scattering and attenuation of radiation. For Bratislava we therefore follow AOD at 550 nm together with PM2.5, PM10 and the European AQI, using the latest complete day 21 August 2026 and the preceding weeks for context. Daily values reveal short aerosol episodes, while the weekly comparisons show whether the situation is persistent or only temporary. At the Department of Optics and Thermophysics of USTARCH SAV, this information is relevant to research on atmospheric light scattering, skyglow, diffuse light and daylight availability. The tables below summarize the current aerosol situation without replacing local in-situ air-quality measurements.<\/p>\n

The first table shows the last 14 complete days for Bratislava<\/strong> and makes it possible to see whether aerosol conditions evolve gradually or in short episodes. AOD at 550 nm describes aerosol optical depth through the atmospheric column, while PM2.5 and PM10 represent concentrations of fine and coarser particles near the surface. The European AQI adds a practical air-quality index, for which the table shows the daily maximum. For optical research it is useful to follow AOD together with particulate matter because aerosols influence scattering and attenuation of radiation. The daily series therefore provides direct context for our modelling of diffuse light and sky brightness.<\/p>\n

How aerosol parameters changed over the last 14 days<\/h3>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Date<\/th>\nAOD 550 nm<\/th>\nPM2.5 (\u00b5g\/m\u00b3)<\/th>\nPM10 (\u00b5g\/m\u00b3)<\/th>\nEuropean AQI \u2013 max<\/th>\n<\/tr>\n<\/thead>\n
8 August 2026<\/th>\n0.228<\/td>\n11.0<\/td>\n12.0<\/td>\n60<\/td>\n<\/tr>\n
9 August 2026<\/th>\n0.190<\/td>\n13.6<\/td>\n14.7<\/td>\n57<\/td>\n<\/tr>\n
10 August 2026<\/th>\n0.250<\/td>\n12.3<\/td>\n17.2<\/td>\n62<\/td>\n<\/tr>\n
11 August 2026<\/th>\n0.163<\/td>\n7.5<\/td>\n10.9<\/td>\n58<\/td>\n<\/tr>\n
12 August 2026<\/th>\n0.092<\/td>\n4.8<\/td>\n6.2<\/td>\n53<\/td>\n<\/tr>\n
13 August 2026<\/th>\n0.071<\/td>\n3.8<\/td>\n4.7<\/td>\n55<\/td>\n<\/tr>\n
14 August 2026<\/th>\n0.074<\/td>\n4.2<\/td>\n5.2<\/td>\n53<\/td>\n<\/tr>\n
15 August 2026<\/th>\n0.070<\/td>\n3.8<\/td>\n4.0<\/td>\n55<\/td>\n<\/tr>\n
16 August 2026<\/th>\n0.255<\/td>\n5.9<\/td>\n6.2<\/td>\n60<\/td>\n<\/tr>\n
17 August 2026<\/th>\n0.473<\/td>\n9.0<\/td>\n9.9<\/td>\n61<\/td>\n<\/tr>\n
18 August 2026<\/th>\n0.215<\/td>\n8.4<\/td>\n8.7<\/td>\n38<\/td>\n<\/tr>\n
19 August 2026<\/th>\n0.185<\/td>\n8.3<\/td>\n8.7<\/td>\n43<\/td>\n<\/tr>\n
20 August 2026<\/th>\n0.195<\/td>\n5.9<\/td>\n6.8<\/td>\n61<\/td>\n<\/tr>\n
21 August 2026<\/th>\n0.226<\/td>\n6.7<\/td>\n9.7<\/td>\n51<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

A single daily value can be affected by short-term weather or air-mass changes, so the second table groups the data into seven-day periods. Weekly means of AOD, PM2.5 and PM10 show more clearly whether elevated or reduced values persist. The maximum AQI within each period also retains information about a short episode that could disappear in the average alone. Comparing four consecutive weeks gives a simple view of the evolution of atmospheric clarity. For our light-scattering research, this smoother time context helps distinguish a one-off episode from a longer-lasting change.<\/p>\n

What the recent weeks show<\/h3>\n
\n\n\n\n\n\n\n\n\n
Period<\/th>\nDays<\/th>\nAOD 550 nm<\/th>\nPM2.5 (\u00b5g\/m\u00b3)<\/th>\nPM10 (\u00b5g\/m\u00b3)<\/th>\nAQI \u2013 maximum<\/th>\n<\/tr>\n<\/thead>\n
15 August 2026 \u2013 21 August 2026<\/th>\n7<\/td>\n0.231<\/td>\n6.9<\/td>\n7.7<\/td>\n61<\/td>\n<\/tr>\n
8 August 2026 \u2013 14 August 2026<\/th>\n7<\/td>\n0.153<\/td>\n8.2<\/td>\n10.1<\/td>\n62<\/td>\n<\/tr>\n
1 August 2026 \u2013 7 August 2026<\/th>\n7<\/td>\n0.250<\/td>\n8.7<\/td>\n9.9<\/td>\n63<\/td>\n<\/tr>\n
25 July 2026 \u2013 31 July 2026<\/th>\n7<\/td>\n0.203<\/td>\n8.0<\/td>\n9.4<\/td>\n60<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

The third table no longer shows absolute values but relative changes, so the direction of development is visible at a glance. The first column compares the latest complete day with the preceding seven-day mean and highlights the current departure. The second compares the latest seven days with the previous seven-day period, making it less sensitive to one extreme day. AOD, PM2.5 and PM10 can evolve differently, so we keep them separate rather than reducing the atmosphere to a single number. This comparison is useful when interpreting conditions that can influence skyglow, diffuse light and daylight availability.<\/p>\n

How the current state differs from recent days<\/h3>\n
\n\n\n\n\n\n\n\n
Indicator<\/th>\nLatest day vs preceding 7-day mean<\/th>\nLatest 7 days vs previous 7 days<\/th>\n<\/tr>\n<\/thead>\n
AOD 550 nm<\/th>\n+7.9%<\/td>\n+51.7%<\/td>\n<\/tr>\n
PM2.5<\/th>\n+3.3%<\/td>\n-16.1%<\/td>\n<\/tr>\n
PM10<\/th>\n+37.6%<\/td>\n-23.8%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
\nMethod note<\/summary>\n

PM2.5 and PM10 use hourly CAMS Global model data; AOD at 550 nm uses CAMS Global. Daily PM and AOD values are means of the hourly data, while daily European AQI is the maximum hourly value. Weekly values are calculated from the daily series. Data are accessed through Open-Meteo and are gridded model values, not a substitute for measurements from local regulatory monitoring stations.<\/p>\n<\/details>\n

Source:<\/strong> Copernicus Atmosphere Monitoring Service (CAMS) via Open-Meteo<\/a>.<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

Aerosols are an important part of the optical state of the atmosphere because they influence scattering and attenuation of radiation. For Bratislava we therefore follow AOD at 550 nm together with PM2.5, PM10 and the European AQI, using the latest complete day 21 August 2026 and the preceding weeks for context. Daily values reveal short aerosol episodes, while the weekly comparisons show whether the situation is persistent or only temporary. At the Department of Optics and Thermophysics of USTARCH SAV, this information is relevant to research on atmospheric light scattering, skyglow, diffuse light and daylight availability. The tables below summarize the current aerosol situation without replacing local in-situ air-quality measurements.<\/p>\n","protected":false},"author":4,"featured_media":8293,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_links_to":"","_links_to_target":""},"categories":[215],"tags":[],"class_list":["post-8205","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-old"],"_links":{"self":[{"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/posts\/8205","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/comments?post=8205"}],"version-history":[{"count":3,"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/posts\/8205\/revisions"}],"predecessor-version":[{"id":8339,"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/posts\/8205\/revisions\/8339"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/media\/8293"}],"wp:attachment":[{"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/media?parent=8205"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/categories?post=8205"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ustarch.sav.sk\/sk\/wp-json\/wp\/v2\/tags?post=8205"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}