Desertification is a serious threat to human development and sustainability. This process is characterized by land degradation over areas with dry sub‐humid, semi‐arid and arid climate. In this work, climate susceptibility to desertification was identified for the state of Rio de Janeiro (SRJ), Brazil, the third most populated state in the country. The state is characterized by complex topography, and diverse climate and land uses. Two formulations for the aridity index were used: I_a, defined by Thornthwaite (1948, Geographical Review, 38(1), 55–94) and Penman (1953, Horticultural Congress, 2, 913–924), and D, a modification of I_a by Hare (1983, Climate and Desertification: A Revised Analysis, Geneva: World Meteorological Organization). Both estimates of the aridity require annual rainfall and potential evapotranspiration, which were calculated from the climatological water balance using times series of rainfall and air temperature (1961–2010) from 98 stations over the SRJ. Annual rainfall, evapotranspiration, water deficit and the aridity indices were then spatially interpolated over a 5 × 5‐km grid using a spline tension method. Both indices agree on the driest regions of the SRJ: Norte and Baixada Litorânea, near the northern coast, both under sub‐humid and semi‐arid climate. The index I_a indicated susceptibility to desertification over 2,305 km² on the Norte and Baixada Litorânea regions, which correspond to 5% of SRJ area; similarly, the index D classified a smaller area over the Norte region under desertification (431 km²). These subregions, among the others also considered in this study, are of great importance for the agricultural, forestry and tourism industries and contribute immensely to the economic development of the state. Hence, the evaluation of susceptibility to desertification in those areas is essential to help prevent further land degradation and support policies formulation on long‐term sustainable management of land and water resources, especially under regional and global climate change scenarios. The methodology used in this work can be applied to studies of desertification in other regions of the world.

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基于干旱指数和地理处理的巴西里约热内卢沙漠化敏感性

荒漠化是对人类发展和可持续性的严重威胁。该过程的特点是在半湿润，半干旱和干旱气候地区土地退化。在这项工作中，确定了巴西第三大人口稠密的州里约热内卢（SRJ）对沙漠化的气候敏感性。该州地势复杂，气候和土地用途多样。使用了两种干旱指数公式：I _a，由Thornthwaite（1948，Geographical Review，38（1），55-94）和Penman（1953，Horticultural Congress，2，913-924）定义，D是修改形式的我_一个由野兔（1983年，气候和荒漠化：经修订的分析，日内瓦：世界气象组织）。干旱的两个估算都需要每年的降雨和潜在的蒸散量，这是根据SRJ上98个站点的降雨和气温（1961-2010）的时间序列，通过气候水平衡计算得出的。然后使用样条拉力法在5×5 km的网格上空间插值年降水量，蒸散量，水分亏缺和干旱指数。两种指数都在SRJ的最干燥地区达成一致：北海岸和北干旱地区的BaixadaLitorânea，处于半湿润和半干旱气候下。指数I _a表示对² 305 km ^2的荒漠化敏感性在北和BaixadaLitorânea地区，相当于SRJ面积的5％；类似地，指数d分类的更小的区域在北下沙漠化区域（431公里²）。这些次区域以及本研究中还考虑的其他次区域，对农业，林业和旅游业具有重要意义，并为国家的经济发展做出了巨大贡献。因此，对这些地区的荒漠化敏感性进行评估对于帮助防止土地进一步退化以及支持制定关于土地和水资源的长期可持续管理的政策至关重要，特别是在区域和全球气候变化情景下。这项工作中使用的方法可以应用于世界其他地区的荒漠化研究。