This indicator shows how many days per year were assessed to have air quality that was worse than “moderate” in Champaign County, according to the U.S. Environmental Protection Agency’s (U.S. EPA) Air Quality Index Reports. The period of analysis is 1980-2024, and the U.S. EPA’s air quality ratings analyzed here are as follows, from best to worst: “good,” “moderate,” “unhealthy for sensitive groups,” “unhealthy,” “very unhealthy,” and "hazardous."[1]

In 2024, the number of days rated to have air quality worse than moderate was 0. This is a significant decrease from the 13 days in 2023 in the same category, the highest in the 21st century. That figure is likely due to the air pollution created by the unprecedented Canadian wildfire smoke in Summer 2023.

While there has been no consistent year-to-year trend in the number of days per year rated to have air quality worse than moderate, the number of days in peak years had decreased from 2000 through 2022. Where peak years before 2000 had between one and two dozen days with air quality worse than moderate (e.g., 1983, 18 days; 1988, 23 days; 1994, 17 days; 1999, 24 days), the year with the greatest number of days with air quality worse than moderate from 2000-2022 was 2002, with 10 days. There were several years between 2006 and 2022 that had no days with air quality worse than moderate.

This data is sourced from the U.S. EPA’s Air Quality Index Reports. The reports are released annually, and our period of analysis is 1980-2024. The Air Quality Index Report websites does caution that "[a]ir pollution levels measured at a particular monitoring site are not necessarily representative of the air quality for an entire county or urban area," and recommends that data users do not compare air quality between different locations[2].

[1] Environmental Protection Agency. (1980-2024). Air Quality Index Reports. (Accessed 13 June 2025).

[2] Ibid.

Source: Environmental Protection Agency. (1980-2024). Air Quality Index Reports. https://www.epa.gov/outdoor-air-quality-data/air-quality-index-report. (Accessed 13 June 2025).

Data on India's Air Quality - state-wise air pollution due to PM 2.5, ozone and solid fuels, deaths due to pollution, and comparison with global peers.

Annual emissions of various air pollutants in the United States have experienced dramatic reductions over the past half a century. As of 2024, emissions of nitrogen oxides (NOx) had reduced by more than ** percent since 1970 to *** million tons. Sulfur dioxide (SO₂) emissions have also fallen dramatically in recent decades, dropping from ** million tons to *** million tons between 1990 and 2024. Air pollutants can pose serious health hazards to humans, with the number of air pollution related deaths in the U.S. averaging ****** a year.

This dataset consists of all contributions made by Social AQI (SAQI) project. The description of dataset is as below -

Local Sensor Data (hyperlocal-air-quality-sensor-data) - contains all sensors values recorded through local neighbourhood sensors throught the length of the project
Locations for all these sensors are as below - In Najafgarh, Delhi, India : Jharoda Kalan, Nangli Dairy and DTC Bus terminal.
In Okhla : Sanjay Colony, Tekhand, Shaheen Bagh.

Data from Central Pollution Control Board (central-air-quality-sensor-data) - Najafgarh_CPCB.csv, Okhla_CPCB.csv : Contains data provided by CPCB from Najafgarh,Delhi and Oklha, Delhi

PollutionODP.owl : Ontology Design Pattern for pollution - http://ontologydesignpatterns.org/wiki/Submissions:Pollution.

Ontology : SAQI ontology as triples (ttl), xml (rdf) and json-ld (json) serialization format
Ontology documentation : ontology/diagram contains figures describing ontology, ontology/documentation/saqi.html contains LODE documentation for the ontology

ethnographic-survey-data - anonymized survey responses for initial pollution perception and literacy survey as well as SAQI app feedback survey.

SHACL-shapes - for validating against SAQI ontology.

sparql-queries - sample queries to run on our ontology.

setup-rdf-store-script - script to setup rdf store with given data using rml mapper.

The compressed package (study code.zip) contains the code files implemented by an under review paper ("Predicting short-term PM2.5 concentrations at fine temporal resolutions using a multi-branch temporal graph convolutional neural network").

Among the study code.zip, main.py is the model code based on a multi-branch temporal graph convolutional neural network. tgcn.py is the temporal graph convolutional network. utils.py contains some functions of graph convolution process. input_data.py is data processing.

The zip file (study data.zip) provides an example of air quality data including PM2.5 concentrations and some meteorological data. input_data.zip also contains a N by N adjacency matrix, which describes the spatial relationship between air quality monitoring stations.

In 2023, the air quality index in Indonesia reached *****, which means that the air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution. Among all provinces in the country, Jakarta had the poorest air quality index that stood at *****. Over the last two decades, Indonesia's air quality has significantly changed, from 1998 to 2016, the country went from being one of the cleaner countries in the world to one of the twenty most polluted.

Air Quality Index: Northern Thailand: Chiang Rai: Wiang, Muang,: PM2.5: High data was reported at 9.500 mcg/Cub m in 18 May 2025. This records a decrease from the previous number of 22.600 mcg/Cub m for 17 May 2025. Air Quality Index: Northern Thailand: Chiang Rai: Wiang, Muang,: PM2.5: High data is updated daily, averaging 22.300 mcg/Cub m from Mar 2024 (Median) to 18 May 2025, with 427 observations. The data reached an all-time high of 275.000 mcg/Cub m in 05 May 2024 and a record low of 6.000 mcg/Cub m in 21 Jul 2024. Air Quality Index: Northern Thailand: Chiang Rai: Wiang, Muang,: PM2.5: High data remains active status in CEIC and is reported by Air Quality and Noise Management Bureau. The data is categorized under Global Database’s Thailand – Table TH.ESG.E: Air Quality Index.

According to the monitoring data from the Embassy of the United States, there was on average 39 micrograms of PM2.5 particles per cubic meter to be found in the air in Beijing during 2023. The air quality has improved considerably since 2013.

Reasons for air pollution in Beijing

China’s capital city Beijing is one of the most populous cities in China with over 20 million inhabitants. Over the past 20 years, Beijing’s GDP has increased tenfold. With the significant growth of vehicles and energy consumption in the country, Beijing’s air quality is under great pressure from the economic development. In the past, the city had a high level of coal consumption. Especially in winter, in which coal consumption increased due to heating, the air quality could get extremely bad on the days without wind. In spring, the wind from the north would bring sand from Mongolian deserts, resulting in severe sandstorms in Beijing. The bad air quality also affected the air visibility and threatened people’s health. On days with very bad air quality, people wearing masks for protection can be seen on the streets in the city.

Methods to improve air quality in Beijing

Over the past years, the government has implemented various methods to improve the air quality in Northern China. Sandstorms, which were quite common 15 years ago, are now rarely seen in Beijing’s spring thanks to afforestation projects on China’s northern borders. The license-plate lottery system was introduced in Beijing to restrict the growth of private vehicles. Large trucks were not allowed to enter certain areas in Beijing. Above all, the coal consumption in Beijing has been restricted by shutting down industrial sites and improving heating systems. Beijing’s efforts to improve air quality has also been highly praised by the UN as a successful model for other cities. However, there is also criticism pointing out that the improvement of Beijing’s air quality is based on the sacrifice of surrounding provinces (including Hebei), as many factories were moved from Beijing to other regions. Besides air pollution, there are other environmental problems like water pollution that China is facing. The industrial transformation is the key to China’s environmental improvement.

This dataset contains trends in days violating air quality standards by date for the Philadelphia-Camden-Wilmington Core-Based Statistical Area (CBSA).In order to convey the health impacts of air pollution to the general public, the US EPA has created a color-coded scale to identify pollutant levels in simple terms. This scale is referred to as the Air Quality Index (AQI). AQI levels are directly related to the federal air quality standards and pollutant concentrations in the air. The AQI reports pollutant levels for six different categories based on AQI: Good or green (0 to 50), Moderate or yellow (51 to 100), Unhealthy for Sensitive Groups or orange (101 to 150), Unhealthy or red (151 to 200), Very Unhealthy or purple (201 to 300), and Hazardous (301 to 500). Note that no day in 2000 or subsequent years has qualified as hazardous, so it is not present in the charts. Sensitive groups are defined as children, older adults, and those with breathing impairments. When the AQI reaches Code Orange or higher for any of the pollutants, an air quality standard violation has occurred.

Air quality standards have been revised a number of times since 1997, and the data in these charts is normalized to the current standard.

This dataset contains quality assured and DOEE-certified air quality data collected from the District’s five air monitoring network sites. The dataset covers a three-year period and includes hourly concentration data points from the Environmental Protection Agency (EPA)’s criteria pollutants, air toxics, and speciation. It also includes hourly surface meteorology data points.

Air Quality Index: Northern Thailand: Chiang Rai: Wiang Phang Kham, Mae Sai: PM2.5: Low data was reported at 7.100 mcg/Cub m in 18 May 2025. This records a decrease from the previous number of 7.700 mcg/Cub m for 17 May 2025. Air Quality Index: Northern Thailand: Chiang Rai: Wiang Phang Kham, Mae Sai: PM2.5: Low data is updated daily, averaging 14.000 mcg/Cub m from Mar 2024 (Median) to 18 May 2025, with 427 observations. The data reached an all-time high of 132.000 mcg/Cub m in 06 Apr 2024 and a record low of 2.000 mcg/Cub m in 23 Aug 2024. Air Quality Index: Northern Thailand: Chiang Rai: Wiang Phang Kham, Mae Sai: PM2.5: Low data remains active status in CEIC and is reported by Air Quality and Noise Management Bureau. The data is categorized under Global Database’s Thailand – Table TH.ESG.E: Air Quality Index.

Air Quality Index: Northern Thailand: Chiang Mai: Sripoom, Muang: PM2.5: High data was reported at 12.700 mcg/Cub m in 18 May 2025. This records an increase from the previous number of 11.200 mcg/Cub m for 17 May 2025. Air Quality Index: Northern Thailand: Chiang Mai: Sripoom, Muang: PM2.5: High data is updated daily, averaging 29.000 mcg/Cub m from Mar 2024 (Median) to 18 May 2025, with 427 observations. The data reached an all-time high of 244.000 mcg/Cub m in 06 Apr 2024 and a record low of 7.000 mcg/Cub m in 08 Nov 2024. Air Quality Index: Northern Thailand: Chiang Mai: Sripoom, Muang: PM2.5: High data remains active status in CEIC and is reported by Air Quality and Noise Management Bureau. The data is categorized under Global Database’s Thailand – Table TH.ESG.E: Air Quality Index.

Air Quality Index: Northern Thailand: Chiang Mai: Suthep, Muang: PM2.5: Avg data was reported at 8.900 mcg/Cub m in 18 May 2025. This records a decrease from the previous number of 12.800 mcg/Cub m for 17 May 2025. Air Quality Index: Northern Thailand: Chiang Mai: Suthep, Muang: PM2.5: Avg data is updated daily, averaging 13.740 mcg/Cub m from Mar 2024 (Median) to 18 May 2025, with 371 observations. The data reached an all-time high of 161.960 mcg/Cub m in 07 Apr 2024 and a record low of 1.710 mcg/Cub m in 14 Dec 2024. Air Quality Index: Northern Thailand: Chiang Mai: Suthep, Muang: PM2.5: Avg data remains active status in CEIC and is reported by Air Quality and Noise Management Bureau. The data is categorized under Global Database’s Thailand – Table TH.ESG.E: Air Quality Index.

OpenAQ has collected 231,965,688 air quality measurements from 8,469 locations in 65 countries. Data are aggregated from 105 government level and research-grade sources. https://medium.com/@openaq/where-does-openaq-data-come-from-a5cf9f3a5c85 Note: this dataset is temporary not updated. We're currently working to update it as soon as possible.Disclaimers:- Some records contain encoding issues on specific characters; those issues are present in the raw API data and were not corrected.- Some dates are set in the future: those issues also come from the original data and were not corrected.

The datasets contains date- and state-wise historically compiled data on air quality (by pollution level) in rural and urban areas of India from the year 2015 , as measured by Central Pollution Board (CPCB) through its daily (24 hourly measurements, taken at 4 PM everyday) Air Quality Index (AQI) reports.

The CPCB measures air quality by continuous online monitoring of various pollutants such as Particulate Matter10 (PM10), Particulate Matter2.5 (PM2.5), Sulphur Dioxide (SO2), Nitrogen Oxide or Oxides of Nitrogen (NO2), Ozone (O3), Carbon Monoxide (CO), Ammonic (NH3) and Lead (Pb) and calculating their level of pollution in the ambient air. Based on the each pollutant load in the air and their associated health impacts, the CPCB calculates the overall Air Pollution in Air Quality Index (AQI) value and publishes the data. This AQI data is then used by CPCB to report the air quality status i.e good, satisfactory, moderate, poor, very poor and severe, etc. of a particular location and their related health impacts because of air pollution.

Air pollution levels in cities vary greatly around the world, though they are typically higher in developing regions. In 2024, the cities of Jakarta and Cairo had an average PM2.5 concentrations of **** and **** micrograms per cubic meter (μg/m³) respectively. By comparison, PM2.5 levels in London and New York were less than ***** μg/m³. Nevertheless, pollution levels in these four major cities are all higher than the World Health Organization's healthy limit, which are set at an annual average of less than **** μg/m³. There are many sources of air pollution, such as energy production, transportation, and agricultural activities.

The graph shows the level of concern about air pollution in Mexico as of May 2019. During a survey, **** percent of the respondents with internet-connected smartphones considered air pollution to be a severe problem in their city or municipality.

Air quality is an environmental issue that impacts everyone in Los Angeles. This activity presents current popular press articles about air pollution and environmental justice and maps and graphs PM pollution in Los Angeles.