New legislation on boat fuel may have unintended consequences
Jesús Areso Salinas
I believe in Nature Based Solutions to the Climate Crisis. Large arid areas are missing only one ingredient to become carbon sinks: MOISTURE
By 2024 the average temperature of the earth's atmosphere has broken all records, far exceeding the 1.5°C limit of the Paris agreement. Preliminary data indicate 1.61°C above the average temperature in the years 1850 -1900.
Even more disconcerting is the rise in the average temperature of the oceans and in particular the North Atlantic Ocean.
And here the yearly average of the North Atlantic temperature.
The 1°C rise in ocean temperature implies an immense amount of stored energy since the thermal inertia of ocean water is far greater than that of the atmosphere (more than 1000 times greater).
The scientific community has been circling around this data trying to find an explanation. Professor James Hansen and his team suggest that the large rise in ocean temperatures is linked to new regulations on sulphur emissions in shipping. https://academic.oup.com/oocc/article/3/1/kgad008/7335889?searchresult=1&login=false
In 2020, following an international agreement, a new standard came into force that sharply reduced the legal sulphur content in ship fuels. From 2020, ship fuels could not contain more than 0.5 % sulphur. Until then the limit was 3.5%. sulphur emissions from ships are toxic. They cause illness and death in humans, as well as serious problems for nature such as acid rain. The reduction of these chemical compounds is therefore welcome and necessary.
But the sulphur molecules (SO2) released into the air had an important effect on the climate. When they crystallise, they form tiny microscopic solids or aerosols that reflect part of the sunlight, increasing the albedo and thus cooling the earth. In addition, these sulphur crystals form condensation nuclei of water droplets and favour the formation of clouds over the oceans. These clouds thus formed had an even greater cooling effect than simple sulphur crystals. Removing the sulphur content from the emissions of merchant ships has reduced the formation of these clouds and suddenly the albedo has been strongly reduced. This explains the unexpected warming of the Earth and in particular in the North Atlantic, the North Pacific and the Mediterranean. In these 3 seas the density of marine traffic is among the highest.
The satellite photo shows the clouds formed following the main sea routes of merchant ships.
The situation is problematic as the Earth is still in a phase of accelerated warming with a positive energy balance of about two watts per square metre (2 W/m2 ), i.e. the energy entering the Earth is greater than the energy leaving it in space. Only a few years ago this positive balance was less than one watt per square metre (1 W/m2 ).
James Hansen and Leon Simmons hypothesise that this increase in the energy balance may be due in part to the reduction of sulphur aerosols and the clouds that these aerosols formed. This has led to a reduction in the Earth's albedo and in particular over the most heavily trafficked oceans: the North Atlantic, the North Pacific and the Mediterranean.
So far only historical data. Let's see what will happen in the coming months.
The countries of the Mediterranean Basin, concerned about the effects of sulphur on the health of the environment and the population, have proposed to go further in reducing this type of emissions. The IMO agreement will enter into force on 1 May 2025.
The International Maritime Organisation (IMO) has reached an agreement to tighten exhaust gas standards for ships to reduce sulphur air pollutants in the Mediterranean by 80% from May 2025. From that date, ships sailing in the Mediterranean will have to further reduce sulphur emissions from the maximum limit of 0.5% proposed by the 2020 legislation to a maximum of 0.1%.
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This may have major consequences on the temperatures that may be reached in the Mediterranean in the summer of 2025. The Mediterranean has already warmed to extreme levels similar to those of a tropical sea by 31 °C. We have seen the consequences in 2023 and 2024 with the Daniel storm that devastated Libya in 2023 and the Dana storm that devastated Valencia in October 2024.
A second reduction of aerosols over the Mediterranean by 80% may have larger effects. While the reduction of toxic gases such as sulphur is laudable, it is also to be hoped that the authorities and the scientific world will anticipate the consequences of new legislation.
Why is nobody talking about this? Is anybody in charge?
The situation we wake up to today is the discovery that greenhouse gases may have a greater global warming effect than expected because the pollutants and aerosols that we release into the atmosphere when we burn our fuels produce a cooling effect and thus mask some of the warming effect.
A similar situation occurs in northern India where there is very high aerosol pollution. This pollution is highly toxic to the public and probably like the rest of the world India will eventually impose legislation to reduce these emissions. The problem is that when this happens the albedo of the region will be greatly reduced and this could lead to a sharp rise in temperatures. During the COVID lockdown in India there was some shutdown of industries and a large reduction in pollution. From some cities it was possible to see the Himalayas, which had not been visible for decades. But this led to a large reduction in albedo which brought the energy balance in the region up to 16 watts per square metre! How much will temperatures in that region rise if toxic aerosols are completely eliminated? Will the temperature rise today be even more dangerous than the toxic pollutants themselves?
What solutions are proposed to this dilemma?
In my opinion we should start considering benign aerosols to replace toxic aerosols.
Crystals of sea salt, sodium chloride or cooking salt in micrometric dimensions constitute natural aerosols. These aerosols are produced especially during storms at sea and like sulphur aerosols increase the albedo and form water condensation nuclei responsible for cloud formation, but they are non-toxic and naturally occurring.
When we breathe in the healthy sea breeze we are inhaling thousands of these marine aerosols.
I propose the use of efficient evaporation methods such as Catabatic Towers and/or Rivers in the Air for ambient cooling and humidification. If on top we use seawater as a cooling agent we can generate saline microcrystals in a natural way. In this way we could replace toxic aerosols with natural aerosols and at the same time avoid unwanted and dangerous temperature rises caused by albedo reduction.
Catabatic Towers
Rivers in the Air
I want to thank Leon Simmons and James Hansen for his effort and dedication in studying this phenomenon and also for trying to spread it.
Ingeniero sénior en ENAIRE
1 个月A very interesting French initiative to tackle the problem of fuels and their contaminants, although it does not solve the problem of aerosols. These types of solutions are the ones that have to be pushed with all our financial capacity, because they are the only way we have left. Una iniciativa francesa muy interesante para atajar el problema de los combustibles y sus contaminantes, aunque no resuelve el problema de los aerosoles. https://www.dhirubhai.net/posts/tftp_ha-ha-ha-mdr-ptdr-lol-vous-%C3%AAtes-dr%C3%B4le-faire-activity-7281952501224927232-bsy8?utm_source=share&utm_medium=member_android Este tipo de soluciones son las que hay que impulsar con toda nuestra capacidad financiera, pues son la unica vía que nos queda.