“Dobbiamo proteggere l’oceano perché l’oceano ci protegge”. Brevi note sul parere del Tribunale internazionale per il diritto del mare in tema di cambiamenti climatici nel contesto delle decisioni giudiziarie in materia ambientale"

The Case Law on the obligations of States with regard to the
environment and, in particular, combating climate change, is being enriched by
new contributions at both the national and supranational levels. In addition to a
series of decisions rendered in contentious cases, there is the Advisory Opinion
No. 31 rendered on 21 May 2024 by the International Tribunal for the Law of the
Sea (ITLOS) at the request of the ‘Commission of Small Island States on Climate
Change and International Law’ (COSIS). This opinion recognised that greenhouse gas (GHG) emissions from human activities are a cause, and therefore a
form, of marine pollution, and that States are therefore obliged to take measures
to prevent, reduce and control such pollution. To summarise, these are the main
points of the opinion: the reaffirmation by the Court of its competence in advisory matters; the need for a precautionary approach, based on current scientific
knowledge; the extension by way of interpretation of the obligations of the United
Nations Convention on the Law of the Sea (UNCLOS) to a case not explicitly
provided for by the affirmation of the necessary interaction between UNCLOS
and climate agreements; the overcoming, consequently, of an interpretation based
instead on the concept of ‘fragmentation’ of international law; the definition of
State due diligence obligations as obligations of conduct; the reaffirmation of the
principle of common but differentiated responsibility between industrialised and
non-industrialised States. The circumstance that UNCLOS says nothing about
GHG emissions and, more generally, about climate change, a circumstance obviously due to the lack of perception, at the time of the Third UN Conference on the Law of the Sea, of the seriousness of the problem, was not considered by the
ITLOS as an obstacle at all. The reasoning followed, on the contrary, was in the
sense of interpretatively extending the obligations under UNCLOS to a case not
explicitly provided for by using first of all the approach of UNCLOS itself on the
matter, since its Part XII is full of references to other conventions. The ITLOS,
relying on the scientific evidence offered by science, in particular the Intergovernmental Panel on Climate Change (IPCC), held that GHG emissions constitute
‘marine pollution’ within the meaning of Article 1(1)(4) of UNCLOS, arguing
on the basis of the systemic integration between the UN climate change treaties
and UNCLOS obligations. The TIDM thus created a link between the law of the
sea and the law of climate change, which is essential in assessing the impact of the
climate crisis on the oceans.
Sommario: 1. La recente giurisprudenza in materia di ambiente e di contrasto ai
cambiamenti climatici. – 2. Il parere consultivo del Tribunale Internazionale
per il Diritto del Mare (TIDM) n. 31 del 21 maggio 2024. La riaffermazione
della propria competenza in materia consultiva. – 3. Segue: la pronuncia nel
merito. – 4. Conclusioni.