# Tag Info

Accepted

### What's causing this high SO2 concentrations in Kazakhstan?

The source of SO2 is the smelter associated with the Jezkazgan (Zhezkazgan, Жезказган) copper mine, mined by Kaz Minerals. The complex also produces sulfuric acid. If you check for the other ...
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### Where do bad smells eventually go?

If you are smelling something, you are inhaling gases, particles, or a combination of the two. They don't normally build up in the atmosphere because of three reasons: transport/dilution (which you ...
• 12.7k
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### What is a temperature inversion and can it trap smog/pollution?

Normally, temperature broadly decreases with altitude, and convection is effective: locally warmer air will rise, and cooler air will fall. A temperature inversion is where the air temperature rises ...
• 1,148

### How do current pollution levels in Los Angeles compare to the 1970s?

The air quality in Los Angeles does not meet federal air quality standards. That being said, the air quality has improved immensely since the 1970s. From the California Air Resource Board, in 1965 ...
• 12.7k
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• 2,641

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

As others have noted, a temperature inversion is a layer where temperature increases with height. This is called an inversion because the normal temperature profile decreases with height. A ...
• 13.9k
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### What's the background concentration of trace gas/pollutants?

Background pollution is what would be measured if no anthropogenic emissions existed. In other words, if you shut off human activity (or avoid the emissions from it), you can measure the background. ...
• 12.7k

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

I think it is important to keep in mind the mechanisms that form PM$_{2.5}$ are different than the mechanisms that form O$_3$. From the data your provided you can draw some simple conclusions: ...
• 8,307

### Why are inversion layers so important in meteorology?

Farrenthope is correct, but I would like to add some detail. An inversion occurs when the air is warmer than the ground. It is called an inversion because it is the opposite of what occurs during the ...
• 8,307
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### Are these plane trails seen from satellite

Under the right conditions (in a basic sense, locally high relative humidity; see also this discussion on this site regarding contrail formation), the clouds initially formed by contrails may persist ...
• 1,104
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### Would home heat pumps provide large benefits against climate change?

The values on the DEFRA table with the column heading $kg\ \ce{N2O}$ already include the global warming potential (GWP) factor of 298, as indicated by a note on the column heading (looking at ...
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### How to remove 'silk braid' noise in satellite data?

Thanks for @Kwinkunks's answer. I have read this paper. And this figure may explain something important. What I have already done is plotting the original data like the first subplot. From Destriped -...
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### Why are inversion layers so important in meteorology?

Temperature inversions are important to meteorology and pollution because they are the boundary for atmospheric mixing. If there is a strong inversion, the air above and below an inversion do not ...
• 12.7k
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### How can I test the Air Quality?

The AQI calculation does not require that all pollutants be measured. Instead, it uses the pollutants that are available and then uses a function (chosen by the overarching regulatory agency) that ...
• 12.7k
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### Convert OMI NO2 Vertical Column Density (molecules/cm^2) into Mixing Ratio (ppm)

No, you shouldn't really do that. A vertical column density (VCD) retrieval provides the user with a representation of the total number of molecules over some vertical slice (e.g. the entire ...
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### How Can Smog in Metropolitan Cities like Delhi & Beijing Be Reduced?

The first thing to do is to stop putting pollution in the air, particularly very small particulate matter that are produced by combustion. For the Beijing Olympic Games of 2008, the Chinese ...
• 20.3k
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### Which particles are classified as PM2.5? How exactly is this defined?

I think answering your questions in reverse will make more sense. The "size" of PM is typically the aerodynamic/inertial impaction size, as you guessed. My standard reference for this is this paper. ...
• 1,361

### Are atmospheric halogen oxides "supposed to be" in the atmosphere? Where do they come from?

Classifying the presence of halogen oxides in the atmosphere as either natural, pollution or mixed bag, would result in mixed bag. Natural sources of halogen oxides include the ocean and volcanoes. ...
• 20.3k
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### Does usual city pollution have effects on relative humidity?

By way of reference, "humidity depends on water vaporization and condensation, which, in turn, mainly depends on temperature". From the information you have supplied in your comments. There are ...
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