Today, the UN’s Intergovernmental Panel on Climate Change (IPCC) published its conclusions on what is needed to avoid the worst impacts climate change. The report reflects the latest climate science from experts around the world. It was commissioned by the 2015 Paris Agreement which concluded that all countries should work together to “hold the increase in the global average temperature to well below 2 °C above pre-industrial levels” and “pursue efforts” to limit the temperature increase to 1.5 °C.
The report stresses that keeping temperature rise to 1.5 °C will avoid many of the adverse impacts that would occur at higher temperatures. On land, the risks of climate-induced impacts on biodiversity and ecosystems are substantially less at 1.5°C global warming than at 2°C. Overshooting 1.5°C could have irreversible impacts on some species and ecosystems, even if global warming eventually returned again 1.5°C.
Ocean ecosystems are likely to fare less well. They are already experiencing big climate-induced changes. For example, the majority of warm water coral reefs (such as the Great Barrier Reef) have already seen a large scale loss of coral abundance and will lose a further 70-90% of cover even at 1.5°C global warming.
The IPCC emphasise that it will be very hard to keep temperature rise to 1.5°C without first overshooting to a higher temperature. The solution is not only to reduce greenhouse gas emissions rapidly to nearly zero but also, at the same time, actively remove carbon dioxide from the atmosphere. Unfortunately, many of the so-called carbon dioxide removal (CDR) technologies pose problems of their own for both nature and food security – especially in poor countries. They typically take either a lot of land, or water, or nutrients, or energy, or money – or several of these together.
Instead of CDR, the RSPB and other nature conservation organisations prefer conserving and enhancing the natural systems which have reliably and sustainably removed carbon dioxide for many millions of years, such as forests and wetlands. Encouragingly, the IPCC report includes four representative emission reduction pathways, one of which employs no artificial CDR but only natural systems. It is also the only pathway that limits warming to 1.5°C instead of first overshooting and then returning to 1.5°C. Let’s hope that governments take the IPCC’s advice.
Nick Upton (rspb-images.com)
The climate change challenge also demands a revolution in the way that we generate and use energy. We need this revolution to take place in harmony with nature which is why we published our Energy Vision to offer options for how this could be achieved. To meet this vision, we believe that as well as massive reduction in the amount of energy we consume and large-scale roll out solar power, we'll need sustained investment in innovative technologies such as floating wind turbines. So, it was disheartening to see last week's announcement from the Crown Estate in relation to possible extensions to existing offshore wind farms reliant on existing fixed wind turbines.
The population impacts of some seabirds due to collision risk from existing turbines is high and we are concerned that coastal seabird numbers, including some threatened species will suffer further if these plans go ahead without further work. New and future plans need to recognise the impact that the increasing number of offshore windfarms are already having on our coastal species. The future of many of our seabirds is looking perilous and we run the risk of our magnificent seabird cities falling gradually silent as a result.
We all want to see more renewable energy being generated, but this must be delivered in harmony with nature not at its expense.
As governments consider the implications of the latest IPCC report, we need them both to fast track their transition to a low carbon economy but also do so in a way that causes least harm to the natural world.