scholarly journals Future streamflow simulation in a snow-dominated Rocky Mountain headwater catchment

2017 ◽  
Vol 49 (4) ◽  
pp. 1172-1190
Author(s):  
Ram P. Neupane ◽  
Jan F. Adamowski ◽  
Joseph D. White ◽  
Sandeep Kumar
Keyword(s):  
Assessment Tool ◽  
Circulation Model ◽  
Rocky Mountain ◽  
Baseline Period ◽  
Global Circulation Model ◽  
Global Circulation ◽  
Seasonal Flow ◽  
The Future ◽  
Variable Precipitation ◽  
Headwater Catchment

Abstract The Rocky Mountains in North America are comprised of headwater snow catchments that provide sustained seasonal flow downstream. Changes in streamflow over the last half century in these basins may be associated with changing climate with increased temperature and variable precipitation, shifting seasonal hydrology. We investigated potential changes in future hydrology in a Rocky Mountain headwater catchment by simulating water budgets of the Athabasca River located in Jasper National Park, Canada. Potential hydrologic changes were predicted using a calibrated version of the Soil and Water Assessment Tool (SWAT). Future discharge and other parts of the catchment water budget were projected based on the global circulation model (GCM) derived from the Special Report on Emission Scenarios (SRES) for the latter part of the century (2081–2099). A projected decrease in future precipitation resulted in reduced mean annual streamflow, by up to 86%, compared to the baseline period for the catchment. Projected summer streamflow decreased from 58 to 39%. Streamflow increased from 13 to 26% during the spring, dampening the dominance of summer peak-flow hydrology. Colder winters for the future scenarios increase the overall proportion of precipitation as winter snowfall. However, dramatically lower precipitation estimated for this basin will drive water limits for the future.

scholarly journals Dengue: recent past and future threats

2015 ◽  
Vol 370 (1665) ◽  
pp. 20130562 ◽  
Author(s):  
David J. Rogers
Keyword(s):  
Circulation Model ◽  
Predictor Variables ◽  
Global Circulation Model ◽  
Recent Past ◽  
Model Accuracy ◽  
Vector Borne Diseases ◽  
Global Circulation ◽  
Model Predictions ◽  
The Future ◽  
Vector Borne

This article explores four key questions about statistical models developed to describe the recent past and future of vector-borne diseases, with special emphasis on dengue: (1) How many variables should be used to make predictions about the future of vector-borne diseases? (2) Is the spatial resolution of a climate dataset an important determinant of model accuracy? (3) Does inclusion of the future distributions of vectors affect predictions of the futures of the diseases they transmit? (4) Which are the key predictor variables involved in determining the distributions of vector-borne diseases in the present and future? Examples are given of dengue models using one, five or 10 meteorological variables and at spatial resolutions of from one-sixth to two degrees. Model accuracy is improved with a greater number of descriptor variables, but is surprisingly unaffected by the spatial resolution of the data. Dengue models with a reduced set of climate variables derived from the HadCM3 global circulation model predictions for the 1980s are improved when risk maps for dengue's two main vectors ( Aedes aegypti and Aedes albopictus ) are also included as predictor variables; disease and vector models are projected into the future using the global circulation model predictions for the 2020s, 2040s and 2080s. The Garthwaite–Koch corr-max transformation is presented as a novel way of showing the relative contribution of each of the input predictor variables to the map predictions.

scholarly journals Exploring Historical and Projection of Drought Periods in Cirebon Regency, Indonesia

2018 ◽  
Vol 68 ◽  
pp. 02007 ◽  
Author(s):  
Nila Ardhyarini H. Pratiwi ◽  
Mahawan Karuniasa ◽  
Djoko Santoso Abi Suroso
Keyword(s):  
Standardized Precipitation Index ◽  
Circulation Model ◽  
Drought Severity ◽  
Climate Data ◽  
Global Circulation Model ◽  
Crop Failure ◽  
Global Circulation ◽  
Weather And Climate ◽  
The Future ◽  
Climatic Information

Climate hazards that affect drought could have an impact on agricultural production. Cirebon Regency as one of West Java's food supply areahas experienced hydrological drought because ofclimate variability. Hence, there were many rice fieldswhich lack of water sources for irrigation and resulted in crop failure. Accordingly, this study aims to explore the historical and projection of drought periods as well as the severity of droughts in Cirebon Regency, Indonesia. Interpretation of weather and climate data and Standardized Precipitation Index (SPI) were employed for methods of this studyby using rainfall data only. Based on baseline data (1986-2017) from Jatiwangi Meteorological Stationand Global Circulation Model (GCM) projection simulation (2020-2045) under the Representative Concentration Pathways (RCP) 4.5 scenario, the SPI analysis results show that the drought periodsare predicted to shift in the future with increasing drought severity. This study concludes that climate variability that affects future dry rainfall will still happen in uncertain month periods.Therefore, climatic information is needed in the vulnerable area to reduce the potential impactsthat will occur in the future.

scholarly journals A Comparative Evaluation of a Mesoscale Model and Atmospheric Global Circulation Model for Air Quality Simulation: A Multiscale, Multisite Evaluation

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
P. Goswami ◽  
J. Baruah
Keyword(s):  
High Resolution ◽  
Mesoscale Model ◽  
Large City ◽  
Circulation Model ◽  
Urban Pollution ◽  
Atmospheric Pollutants ◽  
Scale Model ◽  
Global Circulation Model ◽  
Global Circulation ◽  
Meso Scale

Concentrations of atmospheric pollutants are strongly influenced by meteorological parameters like rainfall, relative humidity and wind advection. Thus accurate specifications of the meteorological fields, and their effects on pollutants, are critical requirements for successful modelling of air pollution. In terms of their applications, pollutant concentration models can be used in different ways; in one, short term high resolution forecasts are generated to predict and manage urban pollution. Another application of dynamical pollution models is to generate outlook for a given airbasin, such as over a large city. An important question is application-specific model configuration for the meteorological simulations. While a meso-scale model provides a high-resolution configuration, a global model allows better simulation of large-sale fields through its global environment. Our objective is to comparatively evaluate a meso-scale atmospheric model (MM5) and atmospheric global circulation model (AGCM) in simulating different species of pollutants over different airbasins. In this study we consider four locations: ITO (Central Delhi), Sirifort (South Delhi), Bandra (Mumbai) and Karve Road (Pune). The results show that both the model configurations provide comparable skills in simulation of monthly and annual loads, although the skill of the meso-scale model is somewhat higher, especially at shorter time scales.

Modeling the response of non-perennial streams to climate change impact: The Bouregreg watershed in Morocco

2021 ◽  
Author(s):  
Anna Maria De Girolamo ◽  
Youssef Brouziyne ◽  
Lahcen Benaabidate ◽  
Aziz Aboubdillah ◽  
Ali El Bilali ◽  
...  
Keyword(s):  
Climate Change ◽  
Assessment Tool ◽  
Swat Model ◽  
Circulation Model ◽  
Hybrid Modeling ◽  
Climate Data ◽  
Global Circulation Model ◽  
Stream Network ◽  
Modeling Framework ◽  
Modeling Approach

<p>The non-perennial streams and rivers are predominant in the Mediterranean region and play an important ecological role in the ecosystem diversity in this region. This class of streams is particularly vulnerable to climate change effects that are expected to amplify further under most climatic projections. Understanding the potential response of the hydrologic regime attributes to climatic stress helps in planning better conservation and management strategies. Bouregreg watershed (BW) in Morocco, is a strategic watershed for the region with a developed non-perennial stream network, and with typical assets and challenges of most Mediterranean watersheds. In this study, a hybrid modeling approach, based on the Soil and Water Assessment Tool (SWAT) model and Indicator of Hydrologic Alteration (IHA) program, was used to simulate the response of BW's stream network to climate change during the period: 2035-2050. Downscaled daily climate data from the global circulation model CNRM-CM5 were used to force the hybrid modeling framework over the study area. Results showed that, under the changing climate, the magnitude of the alteration will be different across the stream network; however, almost the entire flow regime attributes will be affected. Under the RCP8.5 scenario, the average number of zero-flow days will rise up from 3 to 17.5 days per year in some streams, the timing of the maximum flow was calculated to occur earlier by 17 days than in baseline, and the timing of the minimal flow should occur later by 170 days in some streams. The used modeling approach in this study contributed in identifying the most vulnerable streams in the BW to climate change for potential prioritization in conservation plans.</p>

scholarly journals THOR: A NEW AND FLEXIBLE GLOBAL CIRCULATION MODEL TO EXPLORE PLANETARY ATMOSPHERES

2016 ◽  
Vol 829 (2) ◽  
pp. 115 ◽  
Author(s):  
João M. Mendonça ◽  
Simon L. Grimm ◽  
Luc Grosheintz ◽  
Kevin Heng
Keyword(s):  
Circulation Model ◽  
Planetary Atmospheres ◽  
Global Circulation Model ◽  
Global Circulation

scholarly journals True dipole wander

2018 ◽  
Vol 215 (3) ◽  
pp. 1523-1529
Author(s):  
Peter Olson ◽  
Maylis Landeau ◽  
Evan Reynolds
Keyword(s):  
Circulation Model ◽  
Global Circulation Model ◽  
Polar Wander ◽  
Global Circulation ◽  
True Polar Wander ◽  
Symmetric Pattern ◽  
Asymmetric Pattern ◽  
Heterogeneous Mantle ◽  
Geocentric Axial Dipole ◽  
Geomagnetic Dipole

SUMMARY A fundamental assumption in palaeomagnetism is that the geomagnetic field closely approximates a geocentric axial dipole in time average. Here we use numerical dynamos driven by heterogeneous core–mantle boundary heat flux from a mantle global circulation model to demonstrate how mantle convection produces true dipole wander, rotation of the geomagnetic dipole on geologic timescales. Our heterogeneous mantle-driven dynamos show a dipole rotation about a near-equatorial axis in response to the transition in lower mantle heterogeneity from a highly asymmetric pattern at the time of supercontinent Pangea to a more symmetric pattern today. This predicted dipole rotation overlaps with a palaeomagnetically inferred rotation in the opposite direction and suggests that some events previously interpreted as true polar wander also include true dipole wander.

scholarly journals The Use of Radiocarbon Measurements in Atmospheric Studies

Radiocarbon ◽  
1990 ◽  
Vol 32 (1) ◽  
pp. 37-58 ◽  
Author(s):  
M R Manning ◽  
D C Lowe ◽  
W H Melhuish ◽  
R J Sparks ◽  
Gavin Wallace ◽  
...  
Keyword(s):  
Nuclear Power ◽  
Circulation Model ◽  
Current Data ◽  
Atmospheric Methane ◽  
Global Circulation Model ◽  
Fossil Carbon ◽  
Global Circulation ◽  
Methane Source ◽  
Clean Air ◽  
Source Current

14C measured in trace gases in clean air helps to determine the sources of such gases, their long-range transport in the atmosphere, and their exchange with other carbon cycle reservoirs. In order to separate sources, transport and exchange, it is necessary to interpret measurements using models of these processes. We present atmospheric 14CO2 measurements made in New Zealand since 1954 and at various Pacific Ocean sites for shorter periods. We analyze these for latitudinal and seasonal variation, the latter being consistent with a seasonally varying exchange rate between the stratosphere and troposphere. The observed seasonal cycle does not agree with that predicted by a zonally averaged global circulation model. We discuss recent accelerator mass spectrometry measurements of atmospheric 14CH4 and the problems involved in determining the fossil fuel methane source. Current data imply a fossil carbon contribution of ca 25%, and the major sources of uncertainty in this number are the uncertainty in the nuclear power source of 14CH4, and in the measured value for δ14C in atmospheric methane.

Sign in / Sign up

Export Citation Format

Share Document