6. Apr, 2020

After the pandemic: a different world?

With global economic activity ramping down as a result of the coronavirus pandemic, it is hardly surprising that emissions of a variety of gases related to energy and transport would be reduced. Traffic levels in the city were estimated to be down 35% compared with a year ago. Emissions of carbon monoxide, mainly due to cars and trucks, have fallen by around 50% for a couple of days this week according to researchers at Columbia University. The Dutch weather bureau KNMI  has reported a dramatic reduction in dangerous substances such as carbon dioxide and nitrogen dioxide in the Netherlands air as a result of canceled flights, reduced traffic, and economic activity.

The future

One may wonder what will happen when the pandemic is over? Will national governments become more mindful in re-stimulating their economies? Will the post-pandemic period show signs of at least the beginning of a new, more ecologically-based, form of economy? Considering the way our economy up to the present has been dominated by principles of growth and profit, a radically different policy based on the experiences of the pandemic seems unlikely. But since modern technology was to a large extent responsible for the benefits of the industrial and agricultural revolutions, it should also be capable to repair their perversions. 

Our atmosphere contains three essential substances, Nitrogen (N2), Oxygen (O2) and water H2O (a reaction between Hydrogen and Oxygen). Over the past ages, they have merged into a relatively stable compound of gasses,  until the agriculture and industrial revolutions and the rapid growth of the world population started to change things radically. Most significant were the anthropogenic reactive carbon and nitrogen. Here follows a brief overview of the two chemical footprints that have led to an increasing concern about the future of this planet.

The 'footprints'

The carbon footprint. Carbon dioxide (CO2) consists of a carbon atom double-bonded to two oxygen atoms. It occurs naturally in Earth's atmosphere as a trace gas Natural sources of carbon include volcanoes, hot springs, geysers, and acids. Because carbon dioxide is soluble in water, it occurs in lakes, rivers, glaciers, and oceans. The carbon footprint is defined as the total greenhouse gases including the carbon-containing gases carbon dioxide and methane, emitted through the burning of fossil fuels, land clearance and the production and consumption of food, manufactured goods, materials, wood, roads, buildings, transportation, and other services. Since the Industrial revolutions anthropogenic emissions – primarily from the use of fossil fuels and deforestation– have rapidly increased its concentration in the atmosphere, leading to global warming. Carbon dioxide also contributes to ocean acidification because it dissolves in water to form carbonic acid

The nitrogen footprint  Nitrogen gas (N₂) makes up 78% of the air. Together with 21  % oxygen (O2), it forms the air we breathe to stay alive. Nitrogen is also an essential building block for amino acids, proteins, and DNA. Plant growth depends on it; animals and people get it from eating plants or other animals. In compressed air, N2  becomes toxic  (think of Scuba divers getting intoxicated when at greater depth). The same holds for O2 when its partial pressure exceeds  1 Bar (Barometric pressure). The major problems for our atmosphere come not from atmospheric  Nitrogen (N2) but from anthropogenic Nitrogen gases, in particular the Nitrogen oxides NO and NO2, together known as NOx (see insert).  NOx is considered to play an important role in global climate change. Notice that nitric oxide is a particularly potent Greenhouse gas as it is over 300 times more effective at trapping heat in the atmosphere than carbon dioxide. It contributes to the formation of smog and acid rain, particulate matter, as well as affecting tropospheric ozone. Nitrogen oxides (NOx) are typically connected with fossil burning from emissions from industrial combustion and gasoline engines.  

Ammonia is largely associated with the agricultural industry and farming. In consists of one nitrogen atom covalently bound to three or four hydrogen atoms (NH3 and NH4). It is produced naturally in the human body and in nature—in water, soil, and air, even in tiny bacteria molecules by a process called ammonification (see insert). In farming, ammonia is often produced by a mixture of manure droppings and urine in stables. Large quantities of NH4 are produced by modern  (bio) industries, including dairies, poultries,  pig stables, and manure surplus deposits. It's a major component of organic manure. In grassy meadows, where cattle were allowed to roam during spring and summer in earlier days,  the manure and urine are often more spread out, thus producing less ammonia.

Nitrification is a natural biological process by which ammonia (NH4) in the soil is gradually transformed in Nitrites (NO2) and then in Nitrates (NO3) which are released back in the atmosphere,  and converted to atmospheric N2  (called denitrification). NH3 is also present in modern commercial fertilizers. Nitrification inhibitors are now used to stop this process, to save the Ammonia (NH4). This is because nitrification may not be so good for agriculture, leading to a loss of the expensive nitrate fertilizer in the soil. Inhibitors are chemical compounds that slow the nitrification of ammonia, ammonium-containing, or urea-containing fertilizers, which are applied to soil as fertilizers. These inhibitors can help reducing losses of nitrogen in the soil that would otherwise be used by crops.

The use of artificial inorganic fertilizers has increased steadily in the last 50 years, rising almost 20-fold to the current rate of 100 million tonnes of nitrogen per year. These fertilizers are often dry inorganic salt with much nitrogen.  As said, their major constituents are the Nitrogen oxides (NO and NO2). Without commercial fertilizers, it is estimated that about one-third of the food produced now could not be produced.  Excessive use of fertilizer in farming – either in the form of manure of cattle or a commercial fertilizer saturates the soil with phosphates and nitrates which in turn produces pollution trough leakage in groundwater, ditches, lakes, canals, rivers and eventual the oceans.

A solution?

The difficult problem to solve is thus that one needs to grow more food to feed an expanding population while minimizing the problems associated with nitrogen fertilizer use. Nitrogen from fertilizers, effluent from livestock and human sewage boost the growth of algae and cause water pollution. It has also contributed to the estimated 8.2 billion damage bill to the Great Barrier Reef. Animal products carry high nitrogen costs compared to vegetable products. A high-animal-protein diet in humans appears to be driving the nitrogen footprint. For example, the consumption of animal products (in particular beef, not chicken and fish) accounts for 82% of the  Australian nitrogen foodprint.

The solution to the nitrogen and carbon dioxide challenge will need to come from a combination of technological innovation, policy and consumer action. Perhaps another lesson of the current pandemic is than mankind should reconsider the shadow sides of globalization, in particular, its effect on the current economies and creating greater health risks.  As national borders disappear and airline fares are low, people are increasingly free to move, creating new challenges to global health and the risk of spreading viruses.

Another side of globalization is that countries depend increasingly on products imported from other countries. Just think of all the electronics and textile stuff that is imported from Hongkong, Taiwan, and Bangladesh.  Profiting from cheap labor. During economical crises, national economies would also be on the safe side by using new technologies  (such as 3 D printing)  allowing them to make products close to the place where they are needed. The same may hold for agricultural stocks that should primarily serve to feed the own nation,  with eventual surpluses exported when appropriate. In Holland at least this could put an end to the massive (70%) overproduction in bioindustry with its mass chicken, cattle and pig stables, stimulated by the European Union. This would certainly be a  post-pandemic change for the better in the economy.