New Mexico is a state located in the Southwestern region of the United States of America. It is part of the ‘Mountain States’ geographic division that encompasses all states that have the Rocky Mountain range running through them. It is also part of the Four Corners region, sharing this intersection with the other states of Arizona, Utah and Colorado. As well as this, it also faces two Mexican states in its southern portion, giving it a significant amount of shared borders.
It had an estimated population of over 2.09 million people as per a census conducted in 2019, making it the 36th largest state in America according to its population size. With a large amount of its economy focused around industries such as drilling for oil, dryland farming and cattle rearing, retail, scientific research and tech companies, as well as the extraction of certain minerals, there is subsequently a negative effect on the air quality as a result, with many of these industrial processes (particularly ones that utilize large amounts of fuel or disturb masses of earth and dust) assisting in raising the PM2.5 count through the various cities in the state.
Looking at some of the states that were on record over the course of 2020, it can be seen that despite a few periods of the year where the pollution levels rose significantly, many of its cities managed to maintain a good quality of air. To cite some examples, the city of Las Vegas (not to be confused with the one found in Nevada) came in with a PM2.5 reading of 11.4 μg/m³ as its yearly average, a reading that placed it within the ‘good’ pollution ratings bracket. This requires a PM2.5 reading of anywhere between 10 to 12 μg/m³ to be classified as such, indicating that it was only 0.7 units away from being moved up into the next pollution grouping (that of the ‘moderate’ rating, which requires a reading between 12.1 to 35.4 μg/m³).
This placed the city in 1st place out of all cities ranked in New Mexico over the course of 2020, as well as 2021st place out of all cities ranked worldwide. As mentioned, this is not an overtly terrible reading, and the months that came in with higher levels of pollution will be discussed in further detail. New Mexico had one city (Las Vegas) come in with a ‘good’ pollution ranking, whilst the remaining twelve came in within the World Health Organizations (WHO's) target goal of 10 μg/m³ or less.
As touched on briefly, a number of New Mexico’s industrial processes would have an effect on the level of air pollution present throughout the state. These would be ones such as emissions from factories, power plants as well as from fertilizers and livestock. Although there have been changes in recent times regarding emission standards from factories and other similar industrial areas, it still stands to reason that many of them still rely on fossil fuels such as natural gas or diesel for their energy. The combustion of these materials releases large amounts of chemical compounds and hazardous particulate matter into the air, all of which can drive up the PM2.5 levels as well as raising the AQI, or air quality index (which takes into consideration the PM2.5 count as well as other pollutants present in the air).
Other major sources of pollution would be ones such as cars and other smaller personal vehicles. These are synonymous with travelling across many of the states in America, with vast expanses of land as well as insufficient public transport between cities and certain areas making vehicles a necessity for many people. Vehicle ownership is constantly on the rise, and whilst positive changes are being made that put forth or promoted the use of greener vehicles, it still stands to reason that the massive amount of cars on the road at any given time would be releasing large amounts of noxious exhaust fumes, which contain all manner of pollutants and can even create new ones within the atmosphere under the right meteorological conditions.
To compound the situation, there is widespread use of heavy duty vehicles, which include among them lorries and trucks. These vehicles are relied on heavily for both import and exportation of all manner of goods and produce, and due to their great size and weight, as well as often running on diesel fuel, put out even larger amounts of pollution and particulate matter than their smaller counterparts do. Combine this with the fact that even worn down tire treads can throw thousands of tons of microscopic rubber particles into the atmosphere, and it becomes clear that vehicles remain as one of the more insidious contributors to air pollution throughout New Mexico, as well as the rest of the world.
Other polluting sources worth noting are ones such as wildfires, which can occur within the state itself or in adjacent ones, with strong winds often blowing huge clouds of smoke over neighboring states or cities. The smoke and pollution clouds that arise from these sources often contain a far greater amount of harmful chemicals, and as such they present a significant health risk when they do occur. Others include dust generated from mining or any form of extraction, as well as construction sites, demolition areas, road repairs as well as even the burning of firewood or charcoal by inhabitants of the state.
Observing the data collected over the course of 2020, it can be seen that there are certain periods of time in which the air pollution levels rise significantly higher over several cities. To use some cities as examples, the most polluted city of Las Vegas saw a depreciation in its air quality levels towards the end of the year. The month of July came in with a very respectable reading of 3.5 μg/m³, which then rose significantly up to 9.9 μg/m³ in August and 9.1 μg/m³ in September. Further elevations were seen in the final two months, with both November and December coming in with significantly poorer readings of 14.9 μg/m³ and 23.2 μg/m³.
These readings placed both of the months into the ‘moderate’ pollution ratings bracket, as well as making December the most polluted month on record for the entire year in both Las Vegas and the state of New Mexico. January and February also presented with moderate ranked pollution readings, coming in at 22.2 μg/m³ and 16.4 μg/m³ respectively, indicating that perhaps meteorological conditions may have played a part in the pollution elevations seen at both the beginning and end of the year.
Other polluted months across the various cities were ones such as January in Taos, which came in with a reading of 14.4 μg/m³ (once again ‘moderate’ due to it being within the 12.1 to 35.4 μg/m³ range). The city of Anthony came in with a reading of 12.3 μg/m³ in October, and to cite a few more, Los Alamos presented with readings of 11.5 μg/m³ and 10.8 μg/m³ in both August and October, as well as the city of Roswell coming in at 10.9 μg/m³ in September. Overall, there were seven months in 2020 that came in with moderate readings across the various cities, another seven that came in with ‘good’ pollution ratings, whilst the rest came in with readings that fell within the WHO's target goal of 10 μg/m³ or less.
In opposition to the previous question, despite there being some rather large spikes of PM2.5 present in some cities, there were also times of the year in other locations where the air quality hit some very respectable levels. Generally, these cleaner readings were seen between the months of March and July, with examples such as 3.5 μg/m³ recorded in Taos in both May and July, as well as Los Alamos coming in at 2.7 μg/m³ and 2.9 μg/m³ over April and May.
Even the most polluted city of 2020 came in with a very good reading of 2.7 μg/m³ in May, and to cite some further examples of the cleanest months on record, the capital city of Santa Fe presented with readings of 2.2 μg/m³ in March, as well as the city of Gallup coming in at 1.7 μg/m³ and 1.9 μg/m³ over the months of April and May. This made April in Gallup the cleanest reading taken in New Mexico over 2020, indicating a time period in which the air would be extremely clean and fresh, free from the many harmful pollutants found in smoke and haze.
Regarding the causes of air pollution as touched upon earlier, there are a number of main pollutants released typically from these sources. They include ones such as volatile organic compounds (VOCs), black carbon, methane (CH4), carbon monoxide (CO) as well as both nitrogen dioxide (NO2) and sulfur dioxide (SO2).
Methane is of particular concern in New Mexico, being a potent greenhouse gas as well as extremely harmful when breathed in over long periods of time or in large quantities. Other concerning pollutants are ones such as ozone (O3), typically created as a secondary pollutant when the various oxides of nitrogen (NOx), as well as many other gases or pollutants, get exposed to sunlight. The ensuing chemical reaction that takes place creates ozone or smog as it is better known when found in large accumulations. Whilst it is a vital component of the upper atmosphere, on ground level it can cause a wide variety of ill health effects to those that are exposed.