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The extreme dry and hot 2015/16 El Niño episode caused large losses in tropical live aboveground carbon (AGC) stocks. Followed by climatic conditions conducive to high vegetation productivity since 2016, tropical AGC are expected to recover from large losses during the El Niño episode; however, the recovery rate and its spatial distribution remain unknown. Here, we used low‐frequency microwave satellite data to track AGC changes, and showed that tropical AGC stocks returned to pre‐El Niño levels by the end of 2020, resulting in an AGC sink of 0.180.140.26$$ {0.18}_{0.14}^{0.26} $$ Pg C year−1 during 2014–2020. This sink was dominated by strong AGC increases (0.610.490.84$$ {0.61}_{0.49}^{0.84} $$ Pg C year−1) in non‐forest woody vegetation during 2016–2020, compensating the forest AGC losses attributed to the El Niño event, forest loss, and degradation. Our findings highlight that non‐forest woody vegetation is an increasingly important contributor to interannual to decadal variability in the global carbon cycle. [ABSTRACT FROM AUTHOR]

Croplands expanded in Africa over recent decades, even though the increasing trends are spatially heterogeneous. The colored lines are the fitted linear change rate (p < .1*, p < .05**, p < .01***) gl The results showed that a large proportion of croplands experienced an increasing trend (54%, 41% with a significant increase, I p i < .1), even though changes in croplands are spatially heterogeneous in Africa. Croplands include cropland (IGBP 12) and cropland and natural vegetation mosaics (IGBP 14) land cover types. [Extracted from the article]

Woody vegetation in global tropical drylands is of significant importance for both the interannual variability of the carbon cycle and local livelihoods. Satellite observations over the past decades provide a unique way to assess the vegetation long-term dynamics across biomes worldwide. Yet, the actual changes in the woody vegetation are always hidden by interannual fluctuations of the leaf density, because the most widely used remote sensing data are primarily related to the photosynthetically active vegetation components. Here, we quantify the temporal trends of the nonphotosynthetic woody components (i.e., stems and branches) in global tropical drylands during 2000-2012 using the vegetation optical depth ( VOD), retrieved from passive microwave observations. This is achieved by a novel method focusing on the dry season period to minimize the influence of herbaceous vegetation and using MODerate resolution Imaging Spectroradiometer ( MODIS) Normalized Difference Vegetation Index ( NDVI) data to remove the interannual fluctuations of the woody leaf component. We revealed significant trends ( P < 0.05) in the woody component ( VODwood) in 35% of the areas characterized by a nonsignificant trend in the leaf component ( VODleaf modeled from NDVI), indicating pronounced gradual growth/decline in woody vegetation not captured by traditional assessments. The method is validated using a unique record of ground measurements from the semiarid Sahel and shows a strong agreement between changes in VODwood and changes in ground observed woody cover ( r2 = 0.78). Reliability of the obtained woody component trends is also supported by a review of relevant literatures for eight hot spot regions of change. The proposed approach is expected to contribute to an improved assessment of, for example, changes in dryland carbon pools. [ABSTRACT FROM AUTHOR]