Remembering Paul Crutzen: A Grand Scientist who took on the Grand Challenges of the Anthropocene

Paul Crutzen, who left us last month, on 28 January 2021, aged 87, was certainly one of the most important Earth system scientists of the Anthropocene. Paul’s work covered a wide range of topics. His earliest work focused on stratospheric ozone chemistry, through which he helped develop an understanding of the potential effects of human activities, including supersonic aircraft, on the Earth’s ozone shield. His work also provided a basis for understanding the Antarctic ozone hole, for which he was awarded the Nobel Prize in Chemistry in 1995, together with Mario Molina and Sherry Rowland.


The “Wicked Problem” of the Covid-19 Pandemic

The current outbreak of the new coronavirus (SARS-CoV-2) will affect virtually every person on Earth, either directly or indirectly. Many people will die of the infectious disease caused by this coronavirus (Covid-19), and others will lose people close to them. Many more will suffer other extreme hardships – psychological, social and financial – due to the extensive physical distancing measures that are reducing the spread of the virus. While there may be some perceived “silver linings”, such as temporarily reduced air pollution and CO2 emissions, and for some an opportunity to slow down and contemplate their ways of living, in the balance the effects are already tremendously challenging for the world, and are likely to get much worse before the pandemic is over.

No Silver Bullet Against Climate Change

The 2018 COP24 climate conference in Katowice, Poland is over. Looking back at what has been achieved in the three years since the historical Paris Agreement reminds me a bit of the John Lennon lyrics: “So this is Christmas - and what have you done? Another year over, and a new one just begun.” While the conference was indeed successful in coming to an agreement over the rule book for how to account for countries upholding their commitments to limiting climate-relevant emissions under the Paris Agreement, there were no real breakthroughs.It is reassuring that the rule book was achieved, despite the considerable resistance from several countries, though it is exactly what was on the plan for this round of negotiations. Thus COP24 was another milestone in the steady progress being made towards implementing measures intended to help us achieve the chief goal of the Paris Agreement: keeping global warming well below 2°C, aiming to limit it to only 1.5°C.