Research into ‘transboundary environmental law’ is rapidly changing, as is environmental law itself. Insights from Earth system science have taught us that we need a planetary approach. Such an approach does not make international law, EU law and domestic law redundant. It does, however, require lawyers working within these legal spheres to look beyond the usual boundaries of legal systems and policy areas. This contribution attempted to show that both at an international and at a domestic level, key players already seem to take a planetary focus when discussing climate change. Climate change, however, is only one of nine planetary boundaries. Our mission for the coming years is to also develop a planetary approach to remain within the other boundaries as well: nitrogen and phosphate flows, ocean acidification, freshwater consumption and the global hydrological cycle, land system change, chemical pollution and the release of novel entities, loss of biosphere integrity, stratospheric ozone depletion and atmospheric aerosol loading. Another major hurdle to take is to look for regime interlinkages across policy fields. The assessment of current instruments under climate law and biodiversity law shows that at the international and the EU level, both regimes are increasingly working together. Progress, however, is terribly slow and there are still areas where both regimes do not speak to each other or are in conflict. Faster and more intense forms of inter-regime collaborations and interactions are needed to fully achieve climate change adaptation, mitigation and biodiversity conservation goals. Inter-regime interactions need to be both broad and deep, ranging from agency collaborations to adopting coordinated or even integrated legal texts. This needs to happen not just at the international level, but also at the EU level and at domestic level. The same can be argued for interlinkages between the other planetary boundaries as well. These challenges are too complex and too interrelated to be addressed without paying attention to transnational regime interlinkages. How exactly such transnational interlinkages should be designed to have the greatest impact still is unclear. Further research and scholarship is needed fill this gap.
Verschuuren, J 2021, Transboundary environmental law scholarship: Towards a focus on planet Earth. in K De Graaf, B Marseille, S Prechal, R Widdershoven & H Winter (eds), Grensoverstijgende rechtsbeoefening: Liber amicorum Jan Jans. Uitgeverij Paris, Zutphen, pp. 329-336.