The resilience of Amazon tree cover to past and present drying

The Amazon forest is increasingly vulnerable to dieback and encroachment of grasslands agricultural fields. Threats these forested ecosystems include drying, deforestation, fire, but feedbacks among make it difficult determine their relative importance. Here, we reconstruct the central western tree cover response aridity fire in mid-Holocene—a time less intensive human land use markedly drier conditions than today—to assess resilience drying strength vegetation-climate feedbacks. We pollen, charcoal, speleothem oxygen isotope proxy data show that mid-Holocene was resilient excess driest bias-corrected future precipitation projections. Experiments with a dynamic global vegetation model (LPJ-GUESS) suggest may be owed weak act amplify loss drying. also compare results observational find that, under limited interference, modern likely similarly levels aridification. Our human-driven deforestation pose greater threat alone.