Recent research claims that global sea levels are rising at a significantly slower rate than previously estimated, contradicting many established scientific projections. The study, spearheaded by Dutch engineering consultant Hessel Voortman and independent researcher Rob de Vos, asserts that the average sea level increase in 2020 was approximately 1.5 mm per year, translating to around 6 inches per century. This figure contrasts sharply with the often-cited rate of 3 to 4 mm per year reported by climate scientists.
Voortman expressed surprise that no prior analysis had compared actual local data with projections. He stated, “It is crazy that it had not been done.” His investigation began in 2021, driven by the question of whether any researchers had conducted such a comparative study.
The recent research stands out as it was conducted without external funding, a rarity in the field. Voortman, who has dedicated over 30 years to hydraulic engineering focused on flood protection and coastal infrastructure, previously published a paper indicating that sea level rise along the low-lying Dutch coast had not accelerated as predicted. He aimed to validate his observations on a global scale, examining data from 200 tide-gauge stations that have been collecting data for at least 60 years.
Voortman noted that for the majority of these stations, the differences between projected and observed sea levels were not statistically significant, suggesting no detectable acceleration in sea level rise. This finding challenges the prevailing narrative that has emerged over the past three decades, particularly following the advent of satellite imagery, which has shown a dramatic increase in sea levels.
He highlighted that sea levels experienced a “trough” in 1993 and reached a “peak” in 2020. When accounting for these fluctuations, the study concludes that there is no significant overall rise in sea levels. In instances where notable increases were detected, Voortman pointed out that these stations were often near others exhibiting minimal changes, leading to skepticism about attributing such rises to a global trend driven by CO2 emissions.
The analysis also critiques the models used by the Intergovernmental Panel on Climate Change (IPCC), suggesting they “significantly overestimate local sea level rise in 2020.” Voortman emphasized the importance of understanding the differences between measurements and projections, particularly in the context of coastal engineering.
He stated, “When designing coastal infrastructure, engineers have long accounted for sea level rise. Both measurements and projections are important sources of information.” Despite his calls for more balanced discourse on sea level rise, Voortman clarified that he does not deny the existence of climate change or the utility of predictive models. He acknowledged their importance in engineering practices, where planning for a technical lifetime of 50 to 100 years necessitates considering future environmental conditions.
As discussions around climate change and its impacts continue to evolve, this study introduces a new perspective that could reshape the understanding of sea level trends and their implications for coastal management.
