Questions tagged [air-pollution]

Air pollution is the introduction of particulates, biological molecules, or other harmful materials into Earth's atmosphere, causing diseases, allergies, death to humans, damage to other living organisms such as animals and food crops, or the natural or built environment.

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What's causing this high SO2 concentrations in Kazakhstan?

I was using this website for weather conditions around the world called Ventusky (https://www.ventusky.com/) and one of its features allows you to view SO2 concentration. I stumbled upon this high ...
gabyarg25's user avatar
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17 votes
1 answer
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Where do bad smells eventually go?

Suppose that I haven't taken a shower for a while, or haven't disposed of my trash, or something, and the room I've been in now stinks. Then, to remove the smell from the room (presumably after first ...
Ove's user avatar
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14 votes
2 answers
432 views

How to remove 'silk braid' noise in satellite data?

Satellite remote sensing data is a powerful tool for researching the spatial distribution and temporal variation of atmospheric species. Aura is one satellite owing to NASA which meaning ...
Han Zhengzu's user avatar
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12 votes
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How to tell the difference between real rain and fake rain (cloud seeding)?

I live in a city where the pollution is bad, so bad that sometimes we get 'fake' rain (from cloud seeding). This may last for an extended period. There have been times before when it has “rained” and ...
Mou某's user avatar
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11 votes
2 answers
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How do current pollution levels in Los Angeles compare to the 1970s?

As I understand it there are two key kinds of air pollution: ozone and fine particles. Are there any long-term data series that chart average ozone levels and/or fine particulates over time going ...
Tyler Durden's user avatar
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10 votes
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How much worse is the typical subway air, compared to street-level air pollution, in a typical city?

An excerpt from a section about the capital of Taiwan, in an article I wrote about Air pollution in Taiwan: Further more, in greater Taipei, the outdoor PM2.5 concentration in the air at ground-...
O0123's user avatar
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10 votes
2 answers
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How do the various types of clouds affect the atmosphere below them in a polluted environment?

I am working through this problem on my own as well, but am feeling that some perspective is in order. So, ignoring the obvious effects where precipitation will wash stuff out of the air, and blocking ...
Jezibelle's user avatar
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10 votes
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What principles do we consider when selecting an air pollution monitor location?

I'm working on a project aiming at finding some potential point as a new air pollutant monitor site for a city to measure $SO_2$, $NO_2$, $PM_{2.5}$, etc. After modeling the surface concentration of ...
Han Zhengzu's user avatar
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9 votes
1 answer
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What's the background concentration of trace gas/pollutants?

I have read a paper discussing the concentration of air pollutants and their background concentration. In the paper Characterization of background air pollution exposure in urban environments using a ...
Han Zhengzu's user avatar
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9 votes
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How can ice crystals with adsorbed chlorine remain over the south pole all winter?

I just saw the Periodic Video Ozone on Bondi Beach - Periodic Table of Videos where the impact of Chlorine from CFCs on Ozone is discussed. At around 04:00 or so, ...
uhoh's user avatar
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What meteorological factors contribute to springtime Trans-Pacific air-pollution events?

The transport of tropospheric ozone, ozone precursors, carbon monoxide, etc from Asia to North America is an active area of research (see J.L. Ambrose, et al., 2011) These types of events occur ...
f.thorpe's user avatar
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8 votes
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Could a reported rainfall pH of 3.1 actually be realistic?

In this Chemistry question Is there any reason to fear personal exposure to rain with a pH of 3.1? I haven't gotten any answer, but there was some discussion about the reality of the measurement. So ...
uhoh's user avatar
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8 votes
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467 views

Monitoring air pollution with Landsat satellite data

I'm trying to build an air pollution model. So far I have built one for point sources. Now I'm looking at monitoring air pollution with satellite images, based on the idea that every basic pollutant ...
ABCD's user avatar
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7 votes
3 answers
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Why are inversion layers so important in meteorology?

I keep hearing the term "inversion layer" when reading about pollution and meteorology. I know it vaguely amounts to "some place where the gradient of temperature is inverted". But why are inversion ...
Jiby's user avatar
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Convert NO2 concentration in Sentinel-5P data from mol/m2 to μg/m3 on the ground level

Sentinel-5P satellite provides high-resolution data products on concentration levels for several atmospheric trace gases (NO2, SO2, O3 , and others), which are measured in mol/m2 within the total or ...
Yaroslav's user avatar
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What causes smog to clear up on some days?

I notice that in my town sometimes the pollution/haze/smog sticks around on some days but then on others the sky can be completely clear. I don't necessarily see any difference between windy and non ...
reddit's user avatar
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7 votes
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How to relate the backward trajectories with offline particular samples?

To correlate chemicals in aerosols emanating from certain sample points, backward trajectory analysis is usually applied for identifying the potential geographical source region. In this figure ...
Han Zhengzu's user avatar
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7 votes
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What's the prospect of air quality forecasting based on machine learning?

Air quality forecasting models which are useful for atmospheric scientist and government can be built based on numerical theory or statistic theory. The first approach outline the basic physics ...
Han Zhengzu's user avatar
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7 votes
0 answers
109 views

Possible new air pollution in town, what to do

Over the last approximately six month an auto parts plant in town has started releasing quite a bit of what smells like paint fumes. When it first started it was pretty rare to get an overwhelming ...
RodgerDodger's user avatar
6 votes
3 answers
17k views

What is a temperature inversion and can it trap smog/pollution?

Just as the title says, I heard about this term but am not sure how it works.
reddit's user avatar
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6 votes
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Which chemicals in smog obscure visibility?

I know that smog is generally a mixture of various chemicals, such as peroxyacetyl nitrate (PAN) and ozone. I also know that smog obscures visibility. My question is two-fold: What chemical in smog ...
BarocliniCplusplus's user avatar
6 votes
2 answers
254 views

How to understand the bizarre high level for both PM2.5 and Ozone

Background Eastern China now (2017.01) are suffering severe haze with striking concentration of PM2.5. Haze, with low visibility and complex chemical components threatens billions of persons' health. ...
Han Zhengzu's user avatar
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6 votes
1 answer
126 views

Would home heat pumps provide large benefits against climate change?

Some facts I have learnt The Global Warming Potential (GWP) was developed to allow comparisons of the global warming impacts of different gases. Specifically, it is a measure of how much energy the ...
Chris Rogers's user avatar
6 votes
2 answers
136 views

What meteorological data is needed for air quality machine learning models?

Are there any studies that discuss what meteorological data I should look at if I am creating an air quality model with machine learning? That is, what should I extract from NCEI or ERA5 first if I ...
Avatrin's user avatar
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6 votes
1 answer
152 views

Are these plane trails seen from satellite

Here are photos from West of Normandy, at 7-9am after sunrise on the 14th of may, from the visible satellite. It's a bit strange that they are visible from space, they are 2-3 miles wide? Are they jet ...
bandybabboon's user avatar
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6 votes
2 answers
162 views

Is pollution a contributing factor to freezing rain?

I have been to different places with nearly the same freezing temperatures, around -2°C, but only at some specific places I repetitively experienced freezing rain. One common factor at these places ...
Anirudh's user avatar
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6 votes
3 answers
70 views

Why does air pollution comes with cold weather in tropical areas?

I reside in Bangkok where the local press have reported several times these two last months November-December about high levels of smog. A similar phenomenon occurred last year in this period (end of ...
anukmenchitlarmen's user avatar
6 votes
1 answer
156 views

Are there standards for tropospheric NO2 levels considered low or high?

I'm working with Ozone Monitoring Instrument (OMI) $\ce{NO_2}$ vertical column density (molecules/cm2) data. To help interpret the values, I'm wondering if there are standards that show which values ...
Rob Marty's user avatar
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6 votes
0 answers
68 views

What is the appropriate name for air pollutant chemical formula like notation?

Consider air pollutants like carbon monoxide and nitrogen dioxide for which we use their chemical formulas, $\ce{CO}$ and $\ce{NO2}$ respectively, as a way to compactly refer to them when writing ...
fire-bee's user avatar
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Dig in the rationality of model evaluation of WRF with land-based station data

I use WRF (Weather research and forecasting) model for in regional scale meteorology simulation. And then, the WRF output files will be deemed as criterial input data applying for chemical transport ...
Han Zhengzu's user avatar
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5 votes
2 answers
858 views

How is the concentration of particulate matter calculated per cubic meter

I have some data about PM10, PM2.5, i.e, how much is generated per day (in kilotonnes) by some sector, say from vehicular emissions. It can be converted to micrograms but I don't know how standard ...
y_159's user avatar
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5 votes
4 answers
296 views

What are the technical solutions to measure $\ce{CO2}$ emissions?

I'm currently at COP24 (United Nations Climate Change Conference) in Katowice, Poland. (some editing since I took a screenshot of my laptop) I've asked some guys about $\ce{CO2}$ emissions but very ...
Mars Robertson's user avatar
5 votes
1 answer
109 views

What meteorological features accompany/cause a thermal inversion?

I am physics grad student working on a problem of making a statistical (neural network) prediction of the air pollution in a city. I am provided with hourly values for ca. a dozen meteo features of ...
NeStack's user avatar
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5 votes
1 answer
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Convert OMI NO2 Vertical Column Density (molecules/cm^2) into Mixing Ratio (ppm)

I want to convert OMI AURA data on NO2 column amounts in molecules/cm2 into ppm for comparison purposes with other literature. Can it be done? Is there a standard way of doing it? I looked into the ...
Francisco's user avatar
5 votes
1 answer
67 views

Clarification of dry deposition of particles

I found a formula for the dry deposition speed of particles and an electric circuit analogy to go with it. I would like some clarification on this figure: I'm mostly interested in the top right ...
theWrongAlice's user avatar
5 votes
1 answer
214 views

Why are "ground level" air quality monitors really on rooftops?

There are many papers that talk about the air quality at ground-level in cities, observed by air quality monitors. Some monitors are located above the building(not actually on the ground). For ...
Han Zhengzu's user avatar
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5 votes
2 answers
728 views

How to map emission inventory from lat&lon corrdinate to WRF model grid

Here, I have a regional emission inventory, which mainly contains the varibales of lat,lon,...
Allen Zhang's user avatar
5 votes
1 answer
103 views

What controls the tendency of trace elements in different particle size fractions?

Trace element atmospheric particles are introduced from different sources, with both anthropogenic and natural origins. By analyzing the concentration levels of 18 elements in samples of $PM_{2.5}$ ...
Han Zhengzu's user avatar
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5 votes
1 answer
86 views

How can methylmercury in the ocean be reabsorbed into the atmosphere?

The Sacramento Bee news article Toxic fog may be poisoning some of California’s mountain lions, study says says Algae in the ocean convert mercury to methylmercury, its most toxic form, which can ...
uhoh's user avatar
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5 votes
3 answers
194 views

After days of smoky air, why is it healthier to stay inside?

A large wildfire has been burning for four days some distance from my town. The air is smoky, but not smokier than yesterday or the day before. General wisdom holds that we should all stay indoors. ...
Travis's user avatar
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5 votes
0 answers
81 views

What are the benefits of direct sun viewing spectrometer over a backscatter measuring spectrometer to quantify trace gases in the atmosphere?

I am using a Pandora spectrometer and a MAX-DOAS spectrometer to quantify the amount of formaldehyde (HCHO) present in the troposphere and stratosphere in Fairbanks, Alaska. Both the spectrometers use ...
Sujai Banerji's user avatar
5 votes
0 answers
386 views

How to explain the diurnal variation for different seasons

In a recent work, I'm trying to figure out the pollution situation of my case area. Dealing with the online equipments, I have got the PM2.5 and PM10 concentration time series for a whole year. I ...
Han Zhengzu's user avatar
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5 votes
0 answers
339 views

How to transform the inventory data from degrees to kilometers

First all, my question was different from the question Converting grid resolution from degrees to kilometers. In chemical transport modeling, the pollutant source inventory was an essential input ...
Han Zhengzu's user avatar
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4 votes
1 answer
354 views

How can agricultural ammonia lead to PM2.5 production in the atmosphere?

The NPR News article Growing Corn Is A Major Contributor To Air Pollution, Study Finds talks about all sources of pollution associated with growing corn, and it singles out the application of ammonia ...
uhoh's user avatar
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4 votes
2 answers
746 views

But what exactly is "black carbon" in the context of snow-melting particulates reaching Antarctica?

CNN's What is black carbon? The latest way humans are causing changes in Antarctica doesn't actually say anything about what black carbon is. Neither does The Guardian's Black carbon pollution from ...
uhoh's user avatar
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4 votes
2 answers
113 views

Estimating meteorological visibility from air chemical and particulate composition

I have found here an answer that provides formula that only takes into account vapors, pressure and temperature - What is the formula used for atmospheric visibility? Is there an approach that also ...
Fima Rotter's user avatar
4 votes
1 answer
896 views

Which particles are classified as PM2.5? How exactly is this defined?

Question When discussing "PM2.5", is there any standardized understanding of which particles are or are not included? Is it everything that's 2.5 microns and smaller? Or Everything between 2....
uhoh's user avatar
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4 votes
2 answers
3k views

Does usual city pollution have effects on relative humidity?

I've noticed that in a rural area with low pollution the relative humidity is constantly lower than the humidity in a high polluted city. Is there any correlation between pollution and humidity?
George I.'s user avatar
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4 votes
3 answers
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Are atmospheric halogen oxides "supposed to be" in the atmosphere? Where do they come from?

I like to naively think of Earth's natural atmosphere as nitrogen, oxygen, argon, water, carbon dioxide and okay, some nitrogen and sulfur oxides, and again okay, a little hydrogen and methane from ...
uhoh's user avatar
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4 votes
1 answer
42 views

How does the WHO calculate the interaction of mortality effects from indoor and outdoor air pollution?

The WHO's landing page on air pollution includes three different estimates of deaths due to air pollution: 7 million total 4.2 million due to outdoor (ambient) air pollution 3.8 due to household (...
LShaver's user avatar
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