Reacción a "Reactions: skeletons of marine sponges suggest that global temperature has already exceeded the 1.5°C limit"

Reconstructing baselines for past climates is fundamentally important so that we understand the uniqueness of our current climate crisis. Skeletons and shells of fossils are an important archive for these changes, and form the basis of this analysis.

“Such studies are challenging, due to small sample numbers, regional settings, and the strong biological modification of the climate signal by organisms which result in uncertainties in proxy, in this study temperature reconstructions. The claim that we might have overshot 1.5C is being made rather confidently, when in fact there are several uncertainties and limitations in this study which must be acknowledged. 

“Such time series will provide a target for our climate models and challenge us to face the realities of climate change altering our world.

“The absolute degree of warming will always depend on the baseline and different groups have different definitions. The absolute number should not be the focus of the discussion, though.  While the Paris Agreement strongly focused on 1.5C, we know that impacts increase with every increment of warming. Missing a target should not say we lose all hope but what we need to increase our efforts. Again, if we miss these target will depend on definitions. One year above 1.5C will allow people and Nature to bounce back. The duration and geographic extend of the overshoot is challenging us as a society to implement the mitigation options we already have and reduce the risks via adaptation.