David Carlin, UNEP-FI:
We are seeing record-breaking heat this June around the world!
2023 is the first-time temperatures have breached the 1.5 C threshold above pre-industrial levels for June. Unfortunately, we can expect these breaches to become more frequent and sustained in the coming years.
We need to recognize that our scientifically critical 1.5 C threshold will break in many ways. It will first be exceeded in short-term averages (e.g., months, seasons) and then in long-term ones (e.g., years, decades).
However, breaches are not a binary thing. Every bit of warming above 1.5 C adds an increasing level of risk, and the longer we remain at elevated temperatures, the greater the risk. Given this scientific reality, each reported breach should motivate us to redouble our efforts to decarbonize and reduce the dangers of climate change to life on earth.
For those who are asking what this means for our net-zero pathways, exceeding 1.5 C levels of warming is not game over. Those pathways are calibrated on end-of-the-century (2100) temperatures, not to a short-run average. A growing share of these pathways assume some level of overshoot before we return temperatures to safe levels (see IPCC AR6 WG3). Overshooting is no free lunch. Overshoots mean a higher level of climate risks and more costly removal of CO2 from the atmosphere before 2100.