Evaluation of Lake Toba's water level decline in Indonesia over the past six decades
Year: 2024
Type: article
Abstract: Lake Toba's water level has significantly declined during the last six decades. Unfortunately, the studies that have been conducted are only sectoral, both in terms of temporal aspects and influencing parameters. Hence, a comprehensive study has been conducted to explain the significant factor causing the Lake Toba's water level decline. Climate change and hydrological issues have become significant concerns. Change point analysis, trend tests, and Structural Equation Model (SEM) were used in this study. Since the results of the analysis show a significant decrease in the water level of Lake Toba in 1984, the discussion of the water level of Lake Toba is divided into two periods, namely Period I (1957–1983) and Period II (1984–2020). This division is also in line with the periods before and after the operation of Siruar Dam. This study revealed that climate change has occurred in the Lake Toba watershed with a significant increasing trend in temperature, evaporation, and rainfall of 0.003 °C, 1.4 mm, and 8.9 mm per year, respectively. Climate factors primarily contributed to the decline in Lake Toba's water level in Period I, whereas the use of water for hydroelectric power plants had a greater impact in Period II. However, with effective regulation of the Siruar Dam during Period II, the water level of Lake Toba has been maintained at a stable level within the predetermined threshold. The study's findings are intended to be useful to the government, stakeholders, and water users in devising mitigation and adaptation measures for the long-term management of Lake Toba's water resources.
Source: Environmental Challenges
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,800
Awards: G3938781544, G6907651227, THIS PROPOSAL BUILDS ON OUR EARLIER WORK (SUPPORTED BY THE PHYSICAL OCEANOGRAPHY PROGRAM) SEARCHING FOR AND ANALYZING THE SIGNATURES OF TIDAL MIXING IN HIGH-RESOLUTION SEA-SURFACE TEMPERATURE DATA. THE CLEAREST SIGNATURE USUALLY ARISES AS A PRONOUNCED SPRING-NEAP TIDAL SIGNAL IN LONG TIME SERIES OF SST DATA. STRONG SPRING-TIDE CURRENTS INDUCE GREATER MIXING THEREBY SLIGHTLY LOWERING SST AS COLD SUBSURFACE WATER TO BROUGHT NEARER THE SURFACE. OUR PREVIOUS WORK CONCENTRATED ON THE INDONESIAN SEAS WHERE WE SHOWED THAT A WELL-KNOWN AND HIGHLY CITED 1996 PAPER BY FFIELD&GORDON GIVES -- OWING TO INADEQUACIES OF SST DATA AVAILABLE TO THEM -- A RATHER MISLEADING PICTURE OF THE TIDAL MIXING IN THAT REGION.
OpenAlex ID: W4405730789