 Estimates from recent literature are cited, giving a potential of up to 5 GtCO2 per year for BECCS and up to 3.6 GtCO2 per year for afforestation.An analysis of the geoengineering proposals published in Nature Communication confirmed findings of the SR15, stating that "all are in early stages of development, involve substantial uncertainties and risks, and raise ethical and governance dilemmas.Based on present knowledge, climate geoengineering techniques cannot be relied on to significantly contribute to meeting the Paris Agreement temperature goals".