MAKNA SUNGAI DALAM RUANG HIDUP YANG BERUBAH: STUDI KASUS DAYAK NGAJU, KALIMANTAN TENGAH

The rivers flow on the island of Borneo have had a significant function for human life since a long time ago. The river has had a role in the dynamics of civilization and environmental evolution in human life until now. With the construction of road infrastructure, the significance of rivers for riverside communities has also changed. This study sees how Ngaju people interpret the river in a living space that changes with development. The research was conducted in two villages which show the characteristics of different locations, society, and development rates. The villages are Talingke village on the bank of the Katingan River and Pangi Village on the bank of the Kahayan River. Data collection were through observation, interviews, and literature study. The study shows that the characteristics of the river area, the community, and the development rates affect the community in interpreting the river. On the one hand, Pangi people start to leave activities in the river, but they still hold the values of the river in their lives. On the other hand, Talingke’s people still focus their activities on the river but no longer have river values in their lives.

Multiscale aspects of the 26–27 April 2011 tornado outbreak. Part I: Outbreak chronology and environmental evolution

One of the most prolific tornado outbreaks ever documented occurred on 26–27 April 2011 and comprised three successive episodes of tornadic convection that primarily impacted the southeastern U.S., including two quasi-linear convective systems (hereafter QLCS1 and QLCS2) that preceded the notorious outbreak of long-track, violent tornadoes spawned by numerous supercells on the afternoon of 27 April. The ~36-h period encompassing these three episodes was part of a longer multiday outbreak that occurred ahead of a slowly moving upper-level trough over the Rocky Mountains. In this Part I, we detail how the environment evolved to support this extended outbreak, with particular attention given to the three successive systems that each exhibited a different morphology and severity.The amplifying upper-level trough and attendant jet streak resulted from a Rossby wave breaking event that yielded a complex tropopause structure and supported three prominent shortwave troughs that sequentially moved into the south-central U.S. QLCS1 formed ahead of the second shortwave and was accompanied by rapid flow modifications, including considerable low-level jet (LLJ) intensification. The third shortwave moved into the lee of the Rockies early on 27 April to yield destabilization behind QLCS1 and support the formation of QLCS2, which was followed by further LLJ intensification and helped to establish favorable deep-layer shear profiles over the warm sector. The afternoon supercell outbreak commenced following the movement of this shortwave into the Mississippi Valley, which was attended by a deep tropopause fold, cold front aloft, and dryline that promoted two prominent bands of tornadic supercells over the Southeast.