Wood Romances

 We're now just past half way through 2023. At the beginning of the year, it was expected that there was a good likelihood that we would transition into El Niño conditions sometime in the Spring or Summer, and this might lead to a new record high GMST in 2024, with a small chance of this happening in 2023. However, with developments occurring over the last couple months, all that has changed. On Twitter, Zeke Hausfather provided data from Berkeley Earth that, barring some event like a large volcanic eruption, there is an  81% chance  that 2023 would beat out 2016/2020 as the warmest year on record. In fact, the year-to-date average already surpasses 2020, and there's a small potential that this year could be the first year to hit the +1.5 ° C above the 1850-1900 mean. Hitting 1.5 ° C would not mean that we have missed the IPCC target of 1.5 ° C, since that target is built on the 30-year average, not a single year. But what changed from the beginning of the year ...

Berkeley Earth just released a new version of the GMST dataset, and it has 4 times the spatial resolution of the previous version of the data set at 0.25° x 0.25° (that's about 30 km at the equator). Visually, the difference is pretty striking when viewing temperature anomalies as a map. Here, for instance are 2022 global temperatures relative to a 1981-2010 mean. The time series has also slightly different from the previous version. Comparing the new high resolution dataset to the previous version, global temperatures in the base period appear to be slightly higher, lowering the amount of current warming above the 1980-1900 mean slightly. However, current warming rates appear to be slightly higher, at about 0.22 °C /decade instead of 0.21 °C /decade for the last 30 years. Here's how 30-year trends have changed across the dataset. To illustrate this, in a recent post , I calculated the warming above the 1850-1900 mean in the three datasets that go back to 1850, and the current ...