scholarly journals Impact of Land Use and Climate Changes on Flood Inundation Areas in the Lower Cimanuk Watershed, West Java Province

2021 ◽  
Vol 23 (2) ◽  
pp. 53-60
Author(s):  
Muhammad Ardiansyah ◽  
Rifqi Aditya Nugraha ◽  
La Ode Syamsul Iman ◽  
Syamsu Dwi Djatmiko

Land use and climatic changes potentially affect the surface runoff and inundation in watershed zones. Every year, the outflow of the Cimanuk River causes floods across the majority of the upper area of the Cimanuk Watershed, as well as the lower area. This study aimed to assess the impact of climatic and land use changes on future flood inundation in the Lower Cimanuk Watershed using a RRI model. Land-use change has been prepared by modeling using a multi-layer perceptron neural network and Markov Chain approach, while climate change using HadGEM2-ES global climate model data under scenarios RCP4.5. In particular, the forest area was projected to decline in this watershed zone, from 19.54% of the total area in 2019 to 17.73% in 2050. Similarly, the area of paddy fields was predicted to decline from approximately 34.36% in 2019 to 29.65% in 2050. In contrast, other types of land use such as dryland agriculture, mixed dryland agriculture, and settlements were projected to increase in the future. The coverage of the simulated flood inundation area using the Rainfall-Runoff Inundation model estimated to reach 179.4 km2 in 2019. The simulation results showed an increase in flood inundation areas in 2030 and 2050, alongside changes in land use and climate. The areas affected by flood inundation were estimated to reach 253.3 km2in 2030. This coverage was expected to increase by 311.9 km2 in 2050, with severely affected land uses including settlements, dry land agriculture, mixed dry land agriculture, paddy fields, and ponds.

2021 ◽  
Author(s):  
Rafael Castro ◽  
Tushar Mittal ◽  
Stephen Self

<p>The 1883 Krakatau eruption is one of the most well-known historical volcanic eruptions due to its significant global climate impact as well as first recorded observations of various aerosol associated optical and physical phenomena. Although much work has been done on the former by comparison of global climate model predictions/ simulations with instrumental and proxy climate records, the latter has surprisingly not been studied in similar detail. In particular, there is a wealth of observations of vivid red sunsets, blue suns, and other similar features, that can be used to analyze the spatio-temporal dispersal of volcanic aerosols in summer to winter 1883. Thus, aerosol cloud dispersal after the Krakatau eruption can be estimated, bolstered by aerosol cloud behavior as monitored by satellite-based instrument observations after the 1991 Pinatubo eruption. This is one of a handful of large historic eruptions where this analysis can be done (using non-climate proxy methods). In this study, we model particle trajectories of the Krakatau eruption cloud using the Hysplit trajectory model and compare our results with our compiled observational dataset (principally using Verbeek 1884, the Royal Society report, and Kiessling 1884).</p><p>In particular, we explore the effect of different atmospheric states - the quasi-biennial oscillation (QBO) which impacts zonal movement of the stratospheric volcanic plume - to estimate the phase of the QBO in 1883 required for a fast-moving westward cloud. Since this alone is unable to match the observed latitudinal spread of the aerosols, we then explore the impact of an  umbrella cloud (2000 km diameter) that almost certainly formed during such a large eruption. A large umbrella cloud, spreading over ~18 degrees within the duration of the climax of the eruption (6-8 hours), can lead to much quicker latitudinal spread than a point source (vent). We will discuss the results of the combined model (umbrella cloud and correct QBO phase) with historical accounts and observations, as well as previous work on the 1991 Pinatubo eruption. We also consider the likely impacts of water on aerosol concentrations and the relevance of this process for eruptions with possible significant seawater interactions, like Krakatau. We posit that the role of umbrella clouds is an under-appreciated, but significant, process for beginning to model the climatic impacts of large volcanic eruptions.</p>


2017 ◽  
Vol 10 (3) ◽  
pp. 1383-1402 ◽  
Author(s):  
Paolo Davini ◽  
Jost von Hardenberg ◽  
Susanna Corti ◽  
Hannah M. Christensen ◽  
Stephan Juricke ◽  
...  

Abstract. The Climate SPHINX (Stochastic Physics HIgh resolutioN eXperiments) project is a comprehensive set of ensemble simulations aimed at evaluating the sensitivity of present and future climate to model resolution and stochastic parameterisation. The EC-Earth Earth system model is used to explore the impact of stochastic physics in a large ensemble of 30-year climate integrations at five different atmospheric horizontal resolutions (from 125 up to 16 km). The project includes more than 120 simulations in both a historical scenario (1979–2008) and a climate change projection (2039–2068), together with coupled transient runs (1850–2100). A total of 20.4 million core hours have been used, made available from a single year grant from PRACE (the Partnership for Advanced Computing in Europe), and close to 1.5 PB of output data have been produced on SuperMUC IBM Petascale System at the Leibniz Supercomputing Centre (LRZ) in Garching, Germany. About 140 TB of post-processed data are stored on the CINECA supercomputing centre archives and are freely accessible to the community thanks to an EUDAT data pilot project. This paper presents the technical and scientific set-up of the experiments, including the details on the forcing used for the simulations performed, defining the SPHINX v1.0 protocol. In addition, an overview of preliminary results is given. An improvement in the simulation of Euro-Atlantic atmospheric blocking following resolution increase is observed. It is also shown that including stochastic parameterisation in the low-resolution runs helps to improve some aspects of the tropical climate – specifically the Madden–Julian Oscillation and the tropical rainfall variability. These findings show the importance of representing the impact of small-scale processes on the large-scale climate variability either explicitly (with high-resolution simulations) or stochastically (in low-resolution simulations).


2016 ◽  
Vol 155 (3) ◽  
pp. 407-420 ◽  
Author(s):  
R. S. SILVA ◽  
L. KUMAR ◽  
F. SHABANI ◽  
M. C. PICANÇO

SUMMARYTomato (Solanum lycopersicum L.) is one of the most important vegetable crops globally and an important agricultural sector for generating employment. Open field cultivation of tomatoes exposes the crop to climatic conditions, whereas greenhouse production is protected. Hence, global warming will have a greater impact on open field cultivation of tomatoes rather than the controlled greenhouse environment. Although the scale of potential impacts is uncertain, there are techniques that can be implemented to predict these impacts. Global climate models (GCMs) are useful tools for the analysis of possible impacts on a species. The current study aims to determine the impacts of climate change and the major factors of abiotic stress that limit the open field cultivation of tomatoes in both the present and future, based on predicted global climate change using CLIMatic indEX and the A2 emissions scenario, together with the GCM Commonwealth Scientific and Industrial Research Organisation (CSIRO)-Mk3·0 (CS), for the years 2050 and 2100. The results indicate that large areas that currently have an optimum climate will become climatically marginal or unsuitable for open field cultivation of tomatoes due to progressively increasing heat and dry stress in the future. Conversely, large areas now marginal and unsuitable for open field cultivation of tomatoes will become suitable or optimal due to a decrease in cold stress. The current model may be useful for plant geneticists and horticulturalists who could develop new regional stress-resilient tomato cultivars based on needs related to these modelling projections.


2010 ◽  
Vol 23 (15) ◽  
pp. 4121-4132 ◽  
Author(s):  
Dorian S. Abbot ◽  
Itay Halevy

Abstract Most previous global climate model simulations could only produce the termination of Snowball Earth episodes at CO2 partial pressures of several tenths of a bar, which is roughly an order of magnitude higher than recent estimates of CO2 levels during and shortly after Snowball events. These simulations have neglected the impact of dust aerosols on radiative transfer, which is an assumption of potentially grave importance. In this paper it is argued, using the Dust Entrainment and Deposition (DEAD) box model driven by GCM results, that atmospheric dust aerosol concentrations may have been one to two orders of magnitude higher during a Snowball Earth event than today. It is furthermore asserted on the basis of calculations using NCAR’s Single Column Atmospheric Model (SCAM)—a radiative–convective model with sophisticated aerosol, cloud, and radiative parameterizations—that when the surface albedo is high, such increases in dust aerosol loading can produce several times more surface warming than an increase in the partial pressure of CO2 from 10−4 to 10−1 bar. Therefore the conclusion is reached that including dust aerosols in simulations may reconcile the CO2 levels required for Snowball termination in climate models with observations.


2020 ◽  
Author(s):  
Alexander Rohrmann ◽  
Guillaume Dupont-Nivet ◽  
Michael Hren ◽  
Dirk Sachse ◽  
Niels Meijer ◽  
...  

<p>At ca. 34 Ma the Eocene-Oligocene transition (EOT) marks the shift from greenhouse conditions during the Eocene to the icehouse of the Oligocene and was the most pronounced cooling event during the Cenozoic. This event is well documented in marine records with a significant increase in benthic foraminifera δ18O values suggesting a 5°C cooling in air temperature through the EOT. Instead, the few but growing number of terrestrial records suggest a much larger cooling of 4-9°C. Yet, details regarding the exact timing of cooling and ensuing terrestrial changes in climate, hydrology, and ecology are sparse. Here, we investigate the impact of the EOT cooling event and associated climatic changes on the hydrology and vegetation in central China. We use stable isotopes of hydrogen (δD<sub>wax</sub>) and carbon (δ<sup>13</sup>C<sub>wax</sub>) from leaf-waxes, a paleo-hydrology proxy obtained from organic material in sedimentary rocks, in combination with pollen data from a continuous well-dated, high-resolution sedimentary section from the Xining Basin in NE Tibet (36°42' N, 101°43' E). We then compare our results to a fully-coupled, global climate model (GCM) simulating the pre- and post-EOT conditions in central Asia.</p><p>The obtained δD<sub>wax </sub>record ranges between -160 to -190‰ and shows a complex two-step transition through the EOT with a rapid initial drop of -30‰ from 33.9 to 33.7 Ma, a recovery to pre-EOT values between 33.7 to 33.4 Ma and a second drop similar in magnitude as the first one. In contrast, δ<sup>13</sup>C<sub>wax</sub> values remain unchanged at -29 to -28‰ through the EOT. The GCM indicates a difference in temperature throughout the year between pre- and post-EOT runs of 8-9°C at the Xining Basin with change in seasonality due to the collapse of the pre-EOT wet spring season, yielding mainly autumn precipitation after the transition. The overall precipitation amount remained in both simulations dry with < 500 mm/yr. The combined results show that the region experienced: (a) a significant temperature drop of 8-9°C through the EOT being the first-order control on the records decrease in δD<sub>wax </sub> (1-2 ‰ per 1°C in mid-latitudes and up-to 5 ‰ per 1°C in higher latitudes) through the EOT; (b) constant bioproductivity and/or similar water-use efficiency within plants displayed by unchanged δ<sup>13</sup>C<sub>wax </sub>values; (c) a changeover from a “warm-wet” desert abundant in Nitraria and Ephedra shrubs to a “temperate” desert with an expansion of conifers and broad-leaf trees in the higher-elevation hinterlands. We interpret that this change in seasonality and cooler EOT temperatures reduced the plant’s overall transpirational pressure, contributing to the spread of conifers and broad-leaf trees after the EOT under regionally new hydrologic conditions.</p>


2020 ◽  
Author(s):  
Paul Kim ◽  
Daniel Partridge ◽  
James Haywood

<p>Global climate model (GCM) ensembles still produce a significant spread of estimates for the future of climate change which hinders our ability to influence policymakers. The range of these estimates can only partly be explained by structural differences and varying choice of parameterisation schemes between GCMs. GCM representation of cloud and aerosol processes, more specifically aerosol microphysical properties, remain a key source of uncertainty contributing to the wide spread of climate change estimates. The radiative effect of aerosol is directly linked to the microphysical properties and these are in turn controlled by aerosol source and sink processes during transport as well as meteorological conditions.</p><p>A Lagrangian, trajectory-based GCM evaluation framework, using spatially and temporally collocated aerosol diagnostics, has been applied to over a dozen GCMs via the AeroCom initiative. This framework is designed to isolate the source and sink processes that occur during the aerosol life cycle in order to improve the understanding of the impact of these processes on the simulated aerosol burden. Measurement station observations linked to reanalysis trajectories are then used to evaluate each GCM with respect to a quasi-observational standard to assess GCM skill. The AeroCom trajectory experiment specifies strict guidelines for modelling groups; all simulations have wind fields nudged to ERA-Interim reanalysis and all simulations use emissions from the same inventories. This ensures that the discrepancies between GCM parameterisations are emphasised and differences due to large scale transport patterns, emissions and other external factors are minimised.</p><p>Preliminary results from the AeroCom trajectory experiment will be presented and discussed, some of which are summarised now. A comparison of GCM aerosol particle number size distributions against observations made by measurement stations in different environments will be shown, highlighting the difficulties that GCMs have at reproducing observed aerosol concentrations across all size ranges in pristine environments. The impact of precipitation during transport on aerosol microphysical properties in each GCM will be shown and the implications this has on resulting aerosol forcing estimates will be discussed. Results demonstrating the trajectory collocation framework will highlight its ability to give more accurate estimates of the key aerosol sources in GCMs and the importance of these sources in influencing modelled aerosol-cloud effects. In summary, it will be shown that this analysis approach enables us to better understand the drivers behind inter-model and model-observation discrepancies.</p>


2015 ◽  
Vol 15 (13) ◽  
pp. 18839-18882 ◽  
Author(s):  
M. Namazi ◽  
K. von Salzen ◽  
J. N. S. Cole

Abstract. A new physically-based parameterization of black carbon (BC) in snow was developed and implemented in the Canadian Atmospheric Global Climate Model (CanAM4.2). Simulated BC snow mixing ratios and BC snow radiative forcings are in good agreement with measurements and results from other models. Simulations with the improved model yield considerable trends in regional BC concentrations in snow and BC snow radiative forcings during the time period from 1950–1959 to 2000–2009. Increases in radiative forcings for Asia and decreases for Europe and North America are found to be associated with changes in BC emissions. Additional sensitivity simulations were performed in order to study the impact of BC emission changes between 1950–1959 and 2000–2009 on surface albedo, snow cover fraction, and surface air temperature. Results from these simulations indicate that impacts of BC emission changes on snow albedos between these two decades are small and not significant. Overall, changes in BC concentrations in snow have much smaller impacts on the cryosphere than the net warming surface air temperatures during the second half of the 20th century.


2016 ◽  
Vol 4 (3) ◽  
pp. 1 ◽  
Author(s):  
Lirih Wigaty ◽  
Samsul Bakri ◽  
Trio Santoso ◽  
Dyah Wulan S. R. Wardani

Ecological disruption as a result of changes in the area of forest cover to other land uses can affect the microclimate and impact toward malaria morbidity.   Malaria is an infectious disease caused by protozoa a genus of Plasmodium that transmitted by female Anopheles sp. mosquito vectors.  The environmental factors that play a role in the risk to transmission of malaria related to vector breeding places.   The purpose of this research is establish the impact of land use changes toward malaria morbidity. This study was conducted from March to September 2015.   Dynamics of land use changes in regency/city be identified through interpretation of landsat imagery in 2002, 2009, and 2014 with supervised classification and resulted in percentage of land use, the influence of impact toward malaria morbidity processed using multiple linear regression models.  Parameter optimization using statistic software.   The result showed that the impact of positive variable that significant toward malaria morbidity are mangrove forest and total population, while impact of negative variable that significant are extensive swamp and health personnel.   Variable which not impact that significant toward malaria morbidity are forests, community forests, undeveloped land, dry land, other land uses, population density, precipitation, unhealthyhousing, urban, and physiographic. Keywords : land use, malaria morbidity


2014 ◽  
Vol 7 (6) ◽  
pp. 7693-7731
Author(s):  
B. Lebassi-Habtezion ◽  
P. Caldwell

Abstract. The ability to run a global climate model in single-column mode is very useful for testing model improvements because single-column models (SCMs) are inexpensive to run and easy to interpret. A major breakthrough in Version 5 of the Community Atmosphere Model (CAM5) is the inclusion of prognostic aerosol. Unfortunately, this improvement was not coordinated with the SCM version of CAM5 and as a result CAM5-SCM initializes aerosols to zero. In this study we explore the impact of running CAM5-SCM with aerosol initialized to zero (hereafter named Default) and test three potential fixes. The first fix is to use CAM5's prescribed aerosol capability, which specifies aerosols at monthly climatological values. The second method is to prescribe aerosols at observed values. The third approach is to fix droplet and ice crystal numbers at prescribed values. We test our fixes in four different cloud regimes to ensure representativeness: subtropical drizzling stratocumulus (based on the DYCOMS RF02 case study), mixed-phase Arctic stratocumulus (using the MPACE-B case study), tropical shallow convection (using the RICO case study), and summertime mid-latitude continental convection (using the ARM95 case study). Stratiform cloud cases (DYCOMS RF02 and MPACE-B) were found to have a strong dependence on aerosol concentration, while convective cases (RICO and ARM95) were relatively insensitive to aerosol specification. This is perhaps expected because convective schemes in CAM5 do not currently use aerosol information. Adequate liquid water content in the MPACE-B case was only maintained when ice crystal number concentration was specified because the Meyers et al. (1992) deposition/condensation ice nucleation scheme used by CAM5 greatly overpredicts ice nucleation rates, causing clouds to rapidly glaciate. Surprisingly, predicted droplet concentrations for the ARM95 region in both SCM and global runs were around 25 cm−3, which is much lower than observed. This finding suggests that CAM5 has problems capturing aerosol effects in this climate regime.


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