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Saat ini bencana hidrometeorologi menunjukkan tren meningkat. Bencana banjir bandang adalah bagian dari bencana hidrometeorologi yang terindikasi berdampak signifikan terhadap kehidupan, dan harta benda.  Faktor utama  banjir bandang adalah dipicu oleh intensitas hujan ekstrim. Kemudian berhubungan dengan kejadian longsor yang menyumbat aliran sungai membentuk bendung alam. Selanjutnya  tekanan aliran sungai menjebol bendung alami tersebut sehingga terjadi banjir bandang yang ditandai dengan kecepatan aliran yang tinggi dengan membawa lumpur, kayu, dan batu. Setidaknya terjadi 10 kejadian banjir bandang di Indonesia pada tahun 2012 yang mengakibatkan 15 korban jiwa dan kerusakan harta benda pada setiap kejadian bencana.  Untuk mengatasi bencana banjir bandang beberapa tindakan mitigasi dapat dilakukan yaitu dengan pemetaan daerah bahaya, sistem peringatan dini, kesiapsiagaan masyarakat, dan peramalan hidrometeorologi. Sayangnya dari upaya tindakan mitigasi tersebut, hanya beberapa daerah yang berpotensi bencana banjir bandang yang siap dengan upaya tersebut.

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[1] Dissolved and particulate organic and inorganic carbon concentrations and flux were measured from July 2005 to June 2006 in the Brantas River basin, a midsized tropical mountainous river and the second largest in Java. There were large seasonal differences in carbon fluxes. Dissolved inorganic carbon (DIC) fluxes were 9.3 times greater and dissolved organic carbon (DOC) fluxes were 532 times greater in the wet season (October to April) than in the dry season. These large contrasts in concentration lead to large differences in load between dry and wet months. In the wet season between January and April, DIC and DOC fluxes are 66% and 87%, respectively, of the total annual fluxes. Most of the annual fluxes of total suspended solids (2.7 Â 106 t a À1 ), total dissolved solids (2.3 Â 106 t a À1 ), DIC (0.26 Â 106 t a À1), and DOC (0.2 Â 106 t a À1 ) are transported into the Madura Strait. Accordingly, the Brantas River ranks number 17 among the top 20 rivers that originate at elevations above 3000 m. The concentration of DIC is consistently high all yearlong due to carbonate weathering in the river basin, except in the middle part of the basin, whereas the concentration of DOC is highly seasonal because of variations in biological activities. The total inorganic carbon concentration substantially exceeded the total organic carbon concentration, but the differences decreased from January to April when DOC increased sharply. The carbon budget indicates that the upstream river is a carbon source, and the middle sections of the river are a carbon sink. No carbon trapping was observed by the several impoundments over the basin while sediment trapping was obvious.

Climate is the crucial determining component in defining the land suitability class for paddy. The paddy suitability class is expected to decrease as a result of global climate change. This study analyzed land suitability for paddy based on the Representative Concentration Pathways (RCP) 4.5 climate projection scenario of Sukabumi Regency in 2020 and 2032 using the Model for Interdisciplinary Research on Climate (MIROC) 5. The parameters analyzed were precipitation (pr), and near-surface air temperature (tas). The global data was adjusted to local conditions using a bias factor calculated using observed climate data from the Meteorological, Climatological, and Geophysical Agency Station in Bandung. Based on the results of this study, climate (precipitation and temperature) projections for Sukabumi Regency in 2020 and 2032 are classified as highly suitable (S1) for paddy cultivation. The result of this study indicates that there would be no change in the climate suitability class for paddy cultivation in Sukabumi Regency between 2020 to 2032. However, the results of this study also identified a significant numerical decline in precipitation. Therefore, we recommend necessary climate change mitigation and adaptation programs to reduce the future risk of decreasing rice production due to crop failure.