Capping atmospheric emissions of, say, carbon dioxide, ammonia, NOx, and so on, should be understood as nothing more than setting and enforcing traffic laws. The same would go for setting limits on nitrogen deposition, from, for example, agricultural activities.

I recently heard this statement defended (as to nitrogen compounds emissions and deposition).

So: the agreements to drive on the left/right side of the road, maximum speeds, priority rules and so on are equivalent to maximum nitrogen deposition caps, such as found in Nitrogen Critical Loads – NCL.

The implication is of course that because everyone must adhere to traffic rules, ‘everyone’ must also adhere to the maximum nitrogen deposition agreements, or carbon dioxide emissions, and so on.

For example, national emission ceilings (NECs) have been set in Directive (EU) 2016/2284 in Europe in which countries must, among other things, emit less NOx and ammonia over a period of several years through national emission reduction commitments.

I will explain here that the traffic analogy in the nitrogen or any other comparable discourse, however attractive, is blatant and dangerous nonsense and profoundly totalitarian, circumventing normal democratic procedures.

Put concisely, traffic conventions are incommensurable to policies, laws, that are based on results ostensibly coming forth from scientific research.

The traffic analogy can only work if these scientific research results are regarded as conventions - agreements - about which no debate is possible, which indeed applies to traffic conventions.

Yet, research results that are presented as indisputable agreements - as we have seen time and time again in the nitrogen discourse in recent years - are by definition outside the scientific order.

As such, the traffic analogy exposes the protective mechanisms of the expertocracy in the nitrogen discourse as to hide the abysmal research qualities of its own work.


What is traffic? Simply put, traffic is the movement of people, animals, objects and so on. This can be done via land - trucks, cars, trains - via water - ships - and via air - planes, helicopters.

I will limit myself to land traffic.

The Convention on Road Traffic is an international treaty designed to facilitate international road traffic and increase road safety through the adoption of uniform traffic rules between countries. 

I will leave aside the imperfections of (any) traffic conventions (agreements), because there will undoubtedly be some. In short, we will keep it simple.

The most basic of traffic rules are: traffic drives on the right side of the road (the left if in the UK, Australia, New Zealand and so on) and adheres to the maximum speeds on different types of roads. Almost everyone adheres to the first rule, but the second rule is a bit more ‘difficult’ in terms of compliance.


The quintessence of capping atmospheric emissions, and in our case deposition of nitrogen compounds, is not emissions/deposition as such but the consequences thereof.

For nitrogen deposition, the heart of the matter is the acidifying, eutrophication and/or biodiversity effects on nature. And here, we immediately run into problems.

Firstly, nitrogen deposition is not measured but modelled, in the Netherlands with the model AERIUS. However, we have proved, using the modellers own data, that AERIUS as a model is a complete failure and must be shelved immediately.

So, nitrogen deposition cannot be determined with any functional precision, let’s just use traffic terminology, who precisely is violating the ‘maximum speed limit’, and where.

Secondly, the nitrogen critical loads (NCL) are, according to the nitrogen expertocracy, the maximum speed limits for habitats. NCL are defined as (Nilsson and Grennfelt, 1988):

“A quantitative estimate of an exposure to one or more pollutants below which significant harmful effects on specified sensitive elements of the environment do not occur according to present knowledge.”

Intriguingly, in the Netherlands, NCL are reported as “unique singular values,” used ostensibly to determine deterioration of ecosystems once N-deposition, as calculated by AERIUS (sic!), exceeds these singular values.

In 2022, my colleague and friend Matt Briggs and myself have shown that NCL are not well defined at all, and are subject to hitherto unrecognised forms of uncertainty that critically impact the precision and actionability of NCL.

Thirdly, notwithstanding AERIUS' ineptness and NCL’s imprecisions and uncertainties unscrupulously obscured by its given numerical exactness, nitrogen is presented as the dominant ecological factor. Thereby many other known ecological pressures are willfully ignored.

Nitrogen deposition ≠ Traffic rules

It must be clear by now that nitrogen emission and deposition limits do not even resemble traffic rules. They are complex expertocratic constructs with countless ambiguities, imperfections and uncertainties for which no one unequivocally can be held accountable.

Nevertheless, nitrogen emission and deposition limits are applied ruthlessly in The Netherlands, and, no doubt, in other countries as well.

The traffic analogy can only work if scientific research results in the nitrogen discourse are regarded as conventions - agreements - about which no debate is possible. This same absurdity goes for the climate discourse.

Be that as it may, research results of any kind that are presented as indisputable agreements are by definition outside the scientific order. As such, the traffic analogy exposes the protective mechanism of the expertocracy in order to hide the abysmal research qualities of its own work.

The fact that there are regular references to the ‘thousands’ of NCL studies that would prove us wrong tragically shows that fallacies - of populism and/or authority - are needed to hide one’s own academic incompetence.

Indeed, we have shown in our study Nitrogen Critical Loads: Critical Reflections on Past Experiments, Ecological Endpoints, and Uncertainties that quite a number of NCL-studies fail on multiple scientific levels.

And here lies the ‘secret’ and the institutional usefulness of the traffic analogy: the Dutch and other governments require everyone to drive ‘right’ on the ‘nitrogen/carbon dioxide/… road’. As with traffic rules, you are not allowed to find fault in that!

Not so!