Best Air Quality vs the Most Polluted Cities in the US

There’s not much that’s more essential than the air we breathe. But our constant inhaling can have negative health effects if we don’t live in one of the cleanest cities in America. While air pollution exists almost everywhere in this post-Industrial Revolution world, it’s often most widespread in well-populated metropolitan areas.

Individual pollutants, such as ozone levels (smog) and particle pollution—or soot—reach the highest levels in the air of the most polluted cities in the US, as the map below shows. In addition to the two most common pollutants, the map contains other types of air pollution like carbon monoxide and lead, along with nitrogen and sulfur dioxide.

View Outdoor Air Quality in the U.S. in a full screen map

Use the map to review the cities with the highest and lowest pollutants, including the 4th highest daily max 8-hour average of ozone levels in the year or the mean PM2.5 weighted by calendar quarter for the year. Or, read on to see what we’ve discovered in the EPA’s data.

Smoggiest Cities in California & More

Photo of smog in downtown L.A. by Metro Library and Archive

While there are many air pollutants (carbon monoxide, lead, nitrogen oxides, and sulfur oxides), two types are more common, especially in cities. One of the most widespread is ozone pollution, otherwise known as smog.

Breathing in smog irritates and inflames the lungs. Unfortunately, more smog or ozone can be found in the air of the following metropolitan areas than anywhere else in the U.S.

  • Riverside-San Bernardino-Ontario, CA – 0.125 ppm
  • Los Angeles-Long Beach-Anaheim, CA – 0.124
  • Bakersfield, CA – 0.101
  • Fresno, CA – 0.09
  • Phoenix-Mesa-Scottsdale, AZ – 0.087
  • Denver-Aurora-Lakewood, CO – 0.087
  • Sacramento–Roseville–Arden-Arcade, CA – 0.086
  • Madera, CA – 0.085
  • Oxnard-Thousand Oaks-Ventura, CA – 0.085
  • Hanford-Corcoran, CA – 0.084

The EPA maintains standards for ozone pollutants and measures a couple of different ways. The results are described in parts per million (ppm). To avoid anomalies, the EPA looks at the 4th highest daily max 8-hour average in the year and sets the standard at 0.07 ppm. All of the top 10 are well beyond that mark and a whopping 70 U.S. cities are above that EPA standard.

Riverside-San Bernardino-Ontario, California area is the dirtiest city in America, at least where smog is concerned. But this isn’t the only Golden State location with abysmally high ozone levels. Home to eight of the top locations, including the four highest, California is one of the most polluted states in the US—and it’s also in the country’s dirtiest region.

Continuing the trend in the western U.S., the Denver-Aurora-Lakewood area ranks high in smog. As does the more southern of the same region (the Phoenix-Mesa-Scottsdale area). Breathing in either smog or soot can increase the risk of lower newborn birth weight, so let’s move on to the second most common air pollutant.

US Cities with the Most Soot in the Air

When it comes to particle pollution (PM2.5, also known as soot), the EPA recommends no more than a 12 ug/m3 mean weighted by calendar quarter for the year. However, 23 cities across the U.S. surpass that—and ten cities’ particles are at far greater levels than the EPA advises, as you’ll see on the table below.

City State PM2.5 Weighted Annual Mean (ug/m3)
Eugene OR 23.2
Bakersfield CA 22.5
San Diego-Carlsbad CA 20.5
Fresno CA 20.3
Hanford-Corcoran CA 19.9
Madera CA 19.1
Phoenix-Mesa-Scottsdale AZ 17.2
Sacramento–Roseville–Arden-Arcade CA 16.1
Chico CA 16
Los Angeles-Long Beach-Anaheim CA 15.9

Once again, Californian cities dominate the charts. Eight of the sootiest are located in California, including many of the top smoggiest cities we mentioned earlier (Bakersfield, Fresno, Hanford-Corcoran, Madera, Sacramento–Roseville–Arden-Arcade, and Los Angeles-Long Beach-Anaheim), along with new additions like San Diego-Carlsbad and Chico.

But none of these cities are #1. That title belongs to Eugene, Oregon, which is nearly double the EPA’s standards.

Find Cities with the Best Air Quality

On a higher note, there are also cities with air quality levels far better than the EPA’s recommendations on the map. Take ozone, of which Urban Honolulu, Hawaii and Santa Cruz-Watsonville, California have the best levels, .045 and .048 ppm, respectively.

The ozone levels of Keene, New Hampshire, Bellingham, Washington, and Claremont-Lebanon, New Hampshire-Vermont are similarly high (.050 ppm). Meanwhile, Minot, North Dakota’s .051 ppm is nearly as good, along with eight cities of .052 ppm, which you can find on the map.

The same goes for particle pollution, which the EPA advises no more than 12 ug/m3:

  • Manchester-Nashua, NH – 3.00 ug/m3
  • Dickinson, ND – 3.60
  • Rock Springs, WY – 3.60
  • Wilmington, NC – 3.70
  • Urban Honolulu, HI – 3.90
  • Laconia, NH – 4.10
  • Claremont-Lebanon, NH-VT – 4.30
  • Corning, NY – 4.40
  • Brainerd, MN – 4.40
  • Cambridge, MD – 4.40
  • Brookings, SD – 4.40

You’ll notice Honolulu, Hawaii and Claremont-Lebanon, New Hampshire have some of the better levels of both smog and soot.


That’s it for the cities with the best and worst air pollution in the U.S. Switching gears from air to recycling, be sure to check out the Most and Least Environmentally Friendly Countries.

550+ Major Plane Crashes

Thousands of people travel to airports every day to catch their flights. It’s an incredibly convenient form of transportation with very little danger. One study from MIT found flying is 19 times safer than driving. Yet even with modern-day planes, disasters like the ones in this post still occur.

We will look at the locations and data from more than 550 of the worst airplane crashes on record. You’ll learn which were the deadliest and what causes were discovered. You needn’t locate each plane’s black box for a flight recording. You’ll find the answers on the map below.

View 550+ Major Plane Crashes in a full screen map

The data comes from the list of plane crashes with 50+ fatalities on Wikipedia. You can sort the map by the total number of deaths, or get more specific with your inquiry about the deaths of crew members, passengers, or people on the ground. Additional sortable groups include type and date, which we’ll also cover below.

10 Deadliest Plane Crashes

Japan Airlines Flight 123

While the map displays aircraft accidents resulting in 50 or more fatalities, many go beyond that (529 of the 553 total disasters fall into the “or more” category). Some even resulted in hundreds or thousands of deaths. For instance, the Japan Airlines Flight 123 is often mentioned when discussing the deadliest aviation accident (520 people died). But three incidents fared worse, as you’ll see below.

  1. American Airlines Flight 11
  2. United Airlines Flight 175
  3. Pan Am Flight 1736 and KLM Flight 4805
  4. Japan Airlines Flight 123
  5. Saudi Arabian Flight 763 and Kazakhstan Airlines Flight 1907
  6. Turkish Airlines Flight 981
  7. Air India Flight 182
  8. Saudia Flight 163
  9. Malaysia Airlines Flight 17
  10. Iran Air Flight 655

Two of the deadliest plane collisions in world history took place on September 11th, 2001. The hijacking of American Airlines Flight 11 resulted in 1,700 deaths, most of which were people inside the North Tower of the World Trade Center. All 81 of the passengers and 11 members of the crew aboard the plane also passed away. The United Airlines Flight 175 hijacking on the same day saw 1,000 people lose their lives. The plane hit the South Tower of the World Trade Center, killing the 56 passengers, nine crew, and countless folks inside the building. These two 9/11 incidents are the only ones with death tolls in the thousands.

After 9/11, the deadliest air crashes include the two flights of Pan Am 1736 and KLM4805 in 1977 along with Japan Airlines Flight 123 (JAL 123) in 1985. While both accidents had death counts in the 500s, the KLM Pan Am crash (also known as the Tenerife airport disaster) was unique in that it involved two planes in a single collision. The two Boeing 747 planes collided on a runway in one of the Canary Islands, resulting in 583 lives lost. As for Japan123, 520 people died aboard the Boeing 747 when, 44 minutes into the flight, it went down near Mount Osutaka in Ueno.

The rest of the 10 deadliest plane crashes saw deaths ranging from 290-349. Notably, Air India Flight 182 (329 deaths) failed due to a bombing. Both Malaysia Airlines Flight 17 (298) and Iran Air Flight 655 (290) were attacked using ground-based weapons. What were some other reasons these jets fell? Let’s find out.

Types of Aviation Accidents

The reasons behind these plane crashes can be divided into six categories or “Types” on the map. Most were accidents or incidents, though 42 were attacks. Let’s break down the specifics of each.

There have been 442 commercial accidents or incidents that brought planes down. The Pan Am 1736 and KLM4805 flights along with Japan Airlines Flight 123 are the two deadliest examples of this type of crash. There have been 44,757 deaths from this most common accident type. There have been 69 accidents or incidents of the military variety, which have combined for 5,989 fatalities. The most deaths in one instance (275) occurred with the Iranian Air Force (15-2280) in 2003.

While less common, attacks such as bombings, ground-based weapon attacks, hijackings, or by other aircrafts can be equally, if not more devastating. Of these attacks, internal bombings, are the most frequent—15 have occurred. The deadliest was the 1985 Air India Flight 182 in which 329 lives were lost. The second-most common aviation attack uses ground-based weapons like ground-to-air missiles or the destruction of the aircraft while on the runway. Thirteen have taken place throughout the years, perhaps most notably were the 298 deaths of Malaysia Airlines Flight 17. To learn more about the 10 hijackings and four attacks by other aircrafts, check out those groups on the map.

More Map Groups

Along with total deaths and the type of incidents that brought them down, you can sort the map by the following:

  • Deaths of crew members, passengers, or ground members
  • Survivor count
  • Incident
  • Aircraft info
  • Phase of fall
  • Airport
  • Dates

These are called groups, as when you map a spreadsheet with BatchGeo, you often have more information than just locations. With additional data, we find the best home. You and users of your map will be able to select only the markers that meet certain requirements, filtering out the rest. Groups can be combined to zero in on very specific results, giving you insight into the story behind the map.

What can you learn from grouping your BatchGeo maps? In addition to understanding the 9/11 attacks were the deadliest in history and that most crashes are commercial, we also discovered the time period(s) that saw the most attacks. 1973 had the most frequent plane collisions, 18 to be exact. Perhaps most relevant today is the month: 58 in December, though July is a close second with 57 accidents.

We also learned most of the planes fell while en route (251 crashes). See the statistics of other phases of flights by grouping the map by that additional data. And for fewer sky-bound accidents, check out 569 Shipwrecks in International Waters.

Change the Google Maps Marker Color (And More) to Match Your Content

Maps display the geographic location of your data on the world. But most aren’t made up of random information jumbled together. There’s often a topic or theme to the data within. Whether the topic is about the Olympics or has a Valentine’s Day theme, you can be sure you continue your map’s cohesive narrative by customizing the Google Maps icon, also known as the map marker, that symbolizes the locations below. This can be done in three ways, via the color, shape, and label of your map marker.

View Largest Wildfires of the Last Decade in a full screen map

So, once you’ve prepared your data for a map, you can begin making your map markers match your content by using shapes and labels. But first, let’s explore how color can create a cohesive narrative.

Create Cohesive Narratives with Color

Say you’re mapping a topic and it’s clear which of two options is good and which is bad. Wouldn’t it be fitting to change Google Map marker color to green for the preferred data and red for the not-so-good? There are many similar cases in which your marker color can help in conveying your data. Check out just one example on our map of working vs. broken McDonald’s ice cream machines below.

View McBroken Los Angeles in a full screen map

Another example of telling a story via a well-thought-out Google Map marker color is selecting yellow, light blue, and orange (to represent gold, silver, and bronze) for a map about every country’s Olympic wins and losses.

View Every Country’s Olympic Wins in a full screen map

And when mapping Valentine’s Day Town Names, it makes sense to use red and pink markers. But for a topic that doesn’t have a natural color association like our examples above, picking the colors of the rainbow will always be pleasing to you and your map’ users’ eyes.

BatchGeo gives you control over the story you tell with your location data, right down to how they’re styled. See all of your marker color choices when you edit your map and click Set Options. Then, Show Advanced Options to check them out. But color customization isn’t the only way to match your content to your map’s style.

Shape Your Map Marker

As with carefully curated colors, the shape of your markers can also hold meaning. While the default Google Maps pin icons might be your go-to option, don’t forget you can mix it up to suit your mapping needs.

For our map of CCTV Cameras by City, we wanted to nix the destination-feel of the pin marker. The rule of thumb is: if it’s not important to pinpoint the exact location on the map, use a marker shape other than the pin. This most often applies to maps of cities, states, or countries.

View CCTV Cameras by City in a full screen map

To change your marker shape when editing your BatchGeo map, scroll to Set Options, Show Advanced Options, and navigate to Marker shape. Square map markers also have their uses and both are better than pins for displaying a marker label.

Identify At A Glance With Labels

A great map marker can only improve your map. And our final tip for getting these great markers involves labels. Best suited for maps with fewer markers, labels enable users to view how many markers there are at a glance.

Plus, as in our map of the 23 largest wildfires, we can quickly determine the largest fire (1) down to the smallest (23) thanks to the numbered labels. Letter labels work the same way.

View Largest Wildfires of the Last Decade in a full screen map

Here’s where to find the label option in BatchGeo. Click Edit Map, then Set Options > Show Advanced Options. To the right of the Advanced options menu, next to “Label each marker” choose between none, letters, and numbers. Once you’ve selected, opt to Map Your Data near the bottom of the page.

Master the three ways of making your map markers match your content: ​​color, shape, and label with BatchGeo.