Whacky Nature Paper Claims That Cleaner Ship Fuels Caused 2023 Global Warming Spike

Hot on the heels of one scientist telling us that Hunga Tonga could not have caused the 2023 sudden global warming spike, we now have a bunch of other scientists telling us that it was the sudden reduction in sulphur content of marine fuels in 2020 wot dunnit. HTDS is real and it is spreading throughout academia like a virus:

If we are not witnessing scientists claiming that, despite Hunga Tonga being able to influence global weather patterns and general circulation for up to 7 years after erupting, it still has negligible effect upon global mean surface temperature, then we are having to endure tortuous and contrived ‘scientific’ explanations of supposedly what did cause the unprecedented and sudden rise in global mean surface temperature starting May/June 2023. This is the latest:

Apparently, it was an “inadvertent geoengineering termination shock” which was responsible for our excursion into global warming “uncharted territory”, not a sudden acceleration of man-made GHG warming and not some “weird El Nino”:

Here’s the abstract of the new study:

Human activities affect the Earth’s climate through modifying the composition of the atmosphere, which then creates radiative forcing that drives climate change. The warming effect of anthropogenic greenhouse gases has been partially balanced by the cooling effect of anthropogenic aerosols. In 2020, fuel regulations abruptly reduced the emission of sulfur dioxide from international shipping by about 80% and created an inadvertent geoengineering termination shock with global impact. Here we estimate the regulation leads to a radiative forcing of +0.2±0.11Wm⁻² averaged over the global ocean. The amount of radiative forcing could lead to a doubling (or more) of the warming rate in the 2020 s compared with the rate since 1980 with strong spatiotemporal heterogeneity. The warming effect is consistent with the recent observed strong warming in 2023 and expected to make the 2020 s anomalously warm. The forcing is equivalent in magnitude to 80% of the measured increase in planetary heat uptake since 2020. The radiative forcing also has strong hemispheric contrast, which has important implications for precipitation pattern changes. Our result suggests marine cloud brightening may be a viable geoengineering method in temporarily cooling the climate that has its unique challenges due to inherent spatiotemporal heterogeneity.

Anthropogenic greenhouse gas warming and its corollary, anthropogenic aerosol cooling are two sides of the same rotten coin: the theory that man-made emissions dominate the radiative imbalance of our planet and that natural variability has little overall effect on global surface temperature, barring short term weather events such as El Nino and La Nina and the odd cooling volcano. It’s a scientific fraud, perhaps the greatest scientific fraud of modern times.

Note that the paper is also advocating marine cloud brightening as a potential geoengineering ‘solution’ to a non existent ‘global boiling’ crisis, having ‘discovered’ how effective sulphur emissions from ships were in keeping the planet from overheating prior to 2020. It’s total bullshit. You can see it’s bullshit just by looking at the graph of expected global mean surface temperature following the introduction of marine fuels legislation in January 2020:

Their modelled estimate of global radiative warming supposedly due to the highly localised and regional lack of emissions of sulphur from ship fuels in northern hemisphere sea lanes completely fails to follow the trajectory of actual global temperature after January 2020. In fact, global surface temperature plunges immediately afterwards, presumably due to the inception of the ‘triple dip’ La Nina, then it recovers very rapidly and suddenly in 2023. The sole basis of the authors’ claim that it was ship fuels which were responsible for the warming in 2023 lies in the fact that the 2023 warming spike coincides with the upper bound in uncertainty of their ‘expected warming’ trend! That’s it. Absurd.

The IMO2020 is expected to provide a substantial boost to the warming rate of global mean temperature in the 2020 s. The rate of warming is expected to ramp up quickly from 2020 and asymptotes to the longer-term trend line at the end of 2020²⁷. The 2023 record warmth is within the ranges of our expected trajectory. The magnitude of IMO2020 induced warming means that the observed strong warming in 2023 will be a new norm in the 2020 s.

The warming did not ramp up quickly after January 2020 - the world cooled - and coincidence in 2023 is not causation!

This is just more politically motivated junk science, junk science moreover which is advocating for Gates’ megalomaniac ‘big idea’ to solve the imaginary ‘climate crisis’ via geoengineering in the form of marine cloud brightening:

The combination of modeled Δ𝑁𝑑 and observed relationship for LWP and cloud fraction adjustments show that IMO2020 as a termination shock for the inadvertent geoengineering experiment of shipping emissions has had a non-trivial warming effect on the climate. The National Academy of Sciences, Engineering, and Medicines⁴ recommended the impact of any outdoor solar radiation management experiment on global mean temperature to be within 1 × 10⁻⁷K. The forcing magnitude of this inadvertent shock has exceeded this limit by a large margin. However, it does suggest that MCB is a viable solar radiation modification scheme in temporarily slowing the rate of climate warming.

Not to be wholly critical though, the authors do at least point out some limitations of their study and do in fact concede that natural variability has a significant role to play in temperature variability and radiative forcing:

We compare the radiative forcing due to IMO2020 and its effect on radiative energy balance with observed changes in relevant quantities. The comparison does not prove causality but provides a context to assess the impact of IMO2020.

. . . . . However, the record since 2020 is too short to ascertain the impact of IMO2020 on the long-term trend of the energy balance given its large interannual variations . . . . .

Another rapid increase period is associated with a phase shift in Pacific Decadal Oscillation (PDO) starting 2014/2015 followed by a strong El-Nino event . . . . .

There are several sources of uncertainties in our estimate of the radiative forcing via cloud dimming induced by IMO2020. A key source is the magnitude of N_d change. Here the N_d change is modeled with a chemical transport model and not constrained with actual observations. The annual mean change in N_d (0.5 cm⁻³) is small compared to the background N_d (28 cm⁻³) and its variability.

But don’t expect any media stories ‘plebsplaining’ the man-made origin of the extraordinary warmth in 2023/24 to a gullible public to point out any of these uncertainties and limitations.