From the planet’s perspective, it’s all good news. Since about 2010, the level of a key fossil-fuel pollutant being pumped into the atmosphere across the Middle East has been steadily falling.
Take a look behind the raw data of a paper published last week in the journal Science Advances and what begins to emerge is an environmental story of a region in two halves.
On the one hand are nations such as the UAE, with the peace and prosperity necessary to make great gains in the war against air pollution.
On the other are those whose reduced production of fossil-fuel gases is involuntary as a product of the political turmoil that has shattered their economies.
To the unblinking, dispassionate eye of the Ozone Monitoring Instrument, orbiting 705 kilometres above earth on the Nasa satellite Aura, it all looks the same.
The OMI’s twin spectrometers measure the amount of man-made nitrogen dioxide being pumped into the atmosphere.
On the neat maps of the Middle East that are generated by the Finnish Meteorological Institute based on OMI’s data, rising levels of nitrogen dioxide are portrayed in various hues of orange and falling levels are shown in blues.
Although we hear much more about the impact of carbon dioxide on global warming, its production is closely linked to that of nitrogen dioxide, which in addition to contributing to climate change, is also directly harmful to human health.
Generally, the amount of nitrogen dioxide detected by the satellite over any spot on Earth is directly related to the use of fossil fuels and the amount of traffic on the roads below.
How much of the stuff any one city or nation is producing has been measured accurately from space since the mid-1990s and in high resolution since the launch of OMI in 2004.
What the two decades of observations tell us is that until about 2010 levels of nitrogen dioxide were rising pretty much everywhere across the Middle East but that since, the trend has gone into reverse across the region.
"The trends in the Middle East are typically larger than in the rest of the world," said Prof Joe Lelieveld, lead author of the paper Abrupt Recent Trend Changes in Atmospheric Nitrogen Dioxide over the Middle East.
“Moreover, it is the only region where strong upward trends before 2010 were followed by strong downward trends in subsequent years.”
It was only when scientists from the Max Planck Institute for Chemistry in Germany and King Saud University in Riyadh set the data in a political and economic context that they found out why there had been such a sharp reverse.
The scientists said that in nations such as the UAE, Saudi Arabia and Kuwait, blessed with the peace and prosperity necessary for progress, the reversal of the nitrogen dioxide trend could be caused by only one thing: a genuine political determination by governments to reduce air pollution.
“Our results provide a first indication that air-quality control in the Arab Gulf states has become effectual,” they concluded.
Prof Lelieveld said that after an earlier survey in 2009, “we could already see quite significant upward trends of nitrogen dioxide emissions in the Gulf.
“So we were revisiting this area in the expectation that we would see upward trends being continued. We were very much surprised to find the reverse.”
This was not, they were sure, merely a hangover from the global economic slump.
“We knew, of course, that there was economic depression but in many countries it was not observed at all in trends of air pollution, and we did not expect this in the Middle East,” he said.
“In fact, there was a quick recovery and we expected that the increase of traffic and use of energy, which is cheap in that region, would lead to more emissions but this was not the case.”
In other countries, such as Syria, Egypt and Iraq, the authors said the downward trend in nitrogen dioxide production was down to “economic recession and upheaval owing to war”.
“Economical crisis and armed conflict have drastically altered the emission landscape of nitrogen oxides in the Middle East,” they said.
It is, they added, “tragic that some of the observed recent negative nitrogen dioxide trends are associated with humanitarian catastrophes”.
Together with the World Bank’s annual global development indicators and data from the US Energy Information Administration, the snapshots of human activity captured by OMI tell the story of the Middle East’s continuing season of despair in coloured maps of the region.
Rising nitrogen dioxide levels over Cairo, bad for the environment but a measure of economic progress, levelled off after 2010, “coincident with the government overthrow in early 2011”.
Economic statistics gathered by the researchers reinforce the point: between 2005 and 2010, GDP in Egypt was increasing at the rate of 6 per cent a year. Since then, it has dropped to 2 per cent, creating economic hardship that has reduced the use of cars and other vehicles.
In Iraq, GDP began to recover within two years of the 2003 invasion, rising by 6 or 7 per cent a year. Unfortunately, economic recovery also boosted nitrogen dioxide levels, by more than 10 per cent a year over Baghdad.
Since 2013, however, nitrogen dioxide production has fallen sharply in Baghdad and central Iraq, including cities such as Tikrit and Samarra, which have been occupied by ISIL.
Declining readings over Iran tell a different story. Here, too, “nitrogen dioxide changes appear to be related to political developments, in this case on an international level”, because of UN Security Council sanctions, imposed in 2006 and extended in 2010.
Nitrogen dioxide levels increased rapidly over the major cities of Tehran and Esfahan between 2005 and 2010, rising by more than 10 per cent a year.
Since then, as sanctions bit deep and GDP suffered, production of nitrogen dioxide has been falling by about 4 per cent a year.
There has also been a recent large reduction in sulphur dioxide levels over the Arabian Gulf, “likely from shipping, in particular near the main Iranian oil tanker terminal at Kharg Island”.
This is explained “by a large drop in oil export of about 50 per cent since 2010”.
After the nuclear deal thrashed out between Iran and world powers in Vienna last month, it will “be interesting to keep track of changes after the sanctions against Iran are lifted in the near future”.
If the causes of falling nitrogen dioxide levels in some parts of the Middle East are depressing, the story in other parts of the region is inspiring.
The paper highlights the length to which some Middle East countries, including the UAE, have gone to reduce their environmental impact.
In particular, it points to the role of a Cabinet decree in 2006, which set tough limits for emissions from vehicles, factories and oil production plants for more than 600 key chemicals and substances, including nitrogen dioxide.
There is a similar story in Saudi Arabia and Kuwait, which have also passed laws governing air quality.
In all three countries, production of nitrogen dioxide increased by about 5 per cent a year between 2005 and 2010, keeping pace, as expected, with GDP, energy production and emissions of carbon dioxide.
Since 2010, however, production of nitrogen dioxide “decreased at approximately the same rate and the positive correlations between economic indicators and nitrogen dioxide emissions have vanished”.
The authors concluded that these “marked trend reversals in the Middle East are unique”.
This suggests that, in their successful efforts to deal with air pollution, the Arabian Gulf states may have set a benchmark to which the rest of the world could, and should, aspire.
The findings have also exposed a false assumption prevalent in pollution science. Until now, many predictions for air pollution and carbon dioxide emissions have assumed a direct relationship between levels of carbon and nitrogen dioxides, said Prof Lelieveld.
“But in the Emirates and other Gulf states we now see that when a country actively implements pollution policies this automatically assumed relationship does not work and this is a lesson we can all learn.”
There is, he said, another lesson to be learnt by governments everywhere.
“This tells us that this type of legislation is working,” said Prof Lelieveld.
“I’m pretty sure that the effects of some of these measures were not known, or at least not quantitatively known, by the policymakers who have implemented them.
“So, for example, there was the Cabinet decree in the Emirates to reduce air pollution and now that effect has actually been observed.
“I hope this will stimulate authorities to do even more because we know now that it works.”
newsdesk@thenational.ae