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Very cool paper! Do u think this is analogous to the European beech system where masting is happening at higher frequency but lower levels due to more rain? From your figure it looks like in both 2018 and 2025 they flowered 2x in 1 yr, which seems wild.

Thanks! Yeah, so when we treat Joshua tree flowering annually, we do see higher frequency of mast years, but don't really get at changing intensity The 2x in one year thing depends on how you define "year"; I think of 2018 and '25 as super-early starts to '19 and '26 doi.org/10.1111/ele....

@joshuajfriedman.com joshua news

Chris helped us perform what's called an attribution analysis: We used @inaturalist.bsky.social records to train a model of Joshua tree flowering based on seasonal weather, then used the model to project Joshua tree flowering from weather simulated under a scenario without climate change.

Working from real weather data, the model correctly predicts flowering in the normal flowering season, Q1 and Q2 for most years (purple areas in the tiny range-maps in this figure); it also correctly predicts documented out-of-season blooms in Q4 of 2018 and 2025!

Chris provided weather data simulated without human-caused climate change, and when we fed that counterfactual weather into the model... it recovered out-of-season blooms in the fourth quarters of 2018 and 2025. Here's just Q4 for each of those years, under factual and counterfactual conditions: