Climate Change Impacts for the Conterminous USA: An Integrated Assessment

Global climate change will impact the hydrologic cycle by increasing the capacity of the atmosphere to hold moisture. Anticipated impacts are generally increased evaporation at low latitudes and increased precipitation at middle and high latitudes. General Circulation Models (GCMs) used to simulate climate disagree on whether the U.S. as a whole and its constituent regions will receive more or less precipitation as global warming occurs. The impacts on specific regions will depend on changes in weather patterns and are certain to be complex. Here we apply the suite of 12 potential climate change scenarios, previously described in Part 1, to the Hydrologic Unit Model of the United States (HUMUS) to simulate water supply in the conterminous United States in reference to a baseline scenario. We examine the sufficiency of this water supply to meet changing demands of irrigated agriculture. The changes in water supply driven by changes in climate will likely be most consequential in the semi-arid western parts of the country where water yield is currently scarce and the resource is intensively managed. Changes of greater than ±50% with respect to present day water yield are projected in parts of the Midwest and Southwest U.S. Interannual variability in the water supply is likely to increase where conditions become drier and to decrease under wetter conditions.     

Accuracy of grid precipitation data for Brazil: application in river discharge modelling of the Tocantins catchment

Here, we compared grid precipitation data — Climate Forecast System Reanalysis (CFSR) and WATCH Forcing Data methodology applied to ERA‐Interim (WFDEI) data — with Brazilian Weather Bureau (INMET) and Brazilian Water Agency (ANA) rain gauge data (n = 2027) for the period 1980–2010 in order to evaluate which grid data set better represents precipitation, and is thus more suitable for hydrological modelling of Brazilian water resources. We found that WFDEI outperformed CFSR according to three statistical indicators. We then applied and interpolated a simple bias correction to further improve WFDEI data before we used these data to model river discharge of the Tocantins catchment with the Soil and Water Assessment Tool (SWAT). Calibration (validation in parentheses; weighted averages of all gauges) had satisfactory statistical metrics: p‐factor = 0.52 (0.47); r‐factor = 0.84 (0.99); R² = 0.78 (0.71); bR² = 0.68 (0.47); NS = 0.70 (0.66); Pbias = ?4.5 (4.0). Finally, the calibrated SWAT model was used to assess the spatial distribution of the catchment's water resources. Annual green water flow (evapotranspiration) increased from the south‐east (640–840 mm yr^?1) to north‐west (1140–1440 mm) of the Tocantins catchment, while green water storage (soil water content) increased from south (330–1070 mm) to north (2180–3290 mm). Blue water (water yield) had a less clear pattern, with lower values in the south and the central borders of the catchment (20–560 mm) and higher values along the central axis and the north (920–1460 mm). Our analysis suggested that WFDEI was an accurate representation of Brazilian precipitation. For large catchments, we therefore recommend the use of WFDEI instead of sparse and often missing rain gauge data in modelling Brazilian water resources. Copyright © 2015 John Wiley & Sons, Ltd.     

The deadliest stable continental region earthquake occurred near Bhuj on 26 January 2001

A large destructive earthquake occurred on 26 January 2001 in the region of Kutch, Gujarat, in Western India, with magnitude Mw 7.7. The earthquake caused very heavy damage and a large number of casualties with more than 20,000 deaths. A preliminary study of ground deformation, damage pattern and aftershock distribution is presented.     

Prediction of inversion strengths and heights from A 1-D nocturnal boundary layer model

A 1-D numerical model for the nocturnal boundary layer is developed which is capable of predicting inversion heights and strengths successfully. The model uses two distinct length scales for the dissipation of turbulent energy and for transfer of heat and momentum within the Planetary Boundary Layer (PBL). The wind and potential temperature profiles obtained from the present model are compared with observations and the agreement is found to be good, viz., the RMSE for inversion height is found to be 71 m and that for inversion strength is found to be 2.0 °C.     

Fortran 77 programs for preliminary summarisation of lineament patterns

Fortran 77 programs have been developed for summarisation of lineament pattern and fracture traces on MS-DOS based micro-computer system. Two menu driven programmes CLAFY and HIST perform the above task. CLAFY reads the X, Y co-ordinates of lineament and points from an input file and produces an output file containing azimuth frequency, total length and average length for 18 predefined azimuth classes at 10 degree interval. HIST reads the output generated by CLAFY and offers an option to generate histograms of azimuth frequency/total length/average length on a dot matric printer. CLAFY and HIST were tested using digitised lineament co-ordinates derived from lineament maps of parts of Central Kerala region, southwestern, India which were prepared based on Landsat imagery interpretation. The programmes afford repetitive manipulation of large quantities of lineament data without ignoring short and /or faint lineaments which have geologic significance.     

Assessment of future stream flow over the Sesan catchment of the Lower Mekong Basin in Vietnam

This study used a regional climate model, driven at a resolution of 30 km, to derive climate estimates that were used as input to a hydrological model to determine stream flow in a changing climate. This regional climate model output was derived using the Weather Research and Forecasting model, which was used to downscale the general circulation model ECHAM5 T63 under the A2 greenhouse gas emission scenario for the future. Two river basins, Dakbla and Poko, over the Sesan catchment of the Lower Mekong region were considered for runoff modeling. A 10‐year climatology of the recent past, 1991–2000, was used as the baseline for the present‐day climate, and another 10‐year climate over the period 2091–2100 was chosen for the future time slice. The results from the simulation of future stream flow indicate that, over both Dakbla and Poko river basins, the stream flow is likely to increase, especially during the peak rainfall season. The Dakbla River Basin shows a substantial increase in stream flow when compared with the Poko River Basin. Copyright © 2011 John Wiley & Sons, Ltd.     

Experimental investigation of Reynolds number effect on vortex induced vibration of rigid circular cylinder on elastic supports

Vortex induced vibration (VIV) of circular cylinders is widely accepted as depending weakly on Reynolds number (Re) and strongly on reduced velocity, mass ratio, and damping. Experiments are conducted in the regime right before transition from laminar to turbulent flow (high-Reynolds 2×l0⁴?4×l0⁴<Re<3.5×l0⁵?6×l0⁶) in the Low Turbulence Channel at the University of Michigan. Limited experimental data are available in that regime. This research was initiated in 2004 studying high-damping VIV to convert hydrokinetic energy from ocean/river currents to electricity using the VIVACE Converter.The following experimental observations are made: low and high Reynolds VIV significantly differ. The range of synchronization of the upper branch increases with increase in Reynolds number. Amplitude ratio (A/D) increases with Reynolds number within the upper branch. For high-Reynolds, A/D=1.9 is achieved routinely in spite of high damping. The lower branch disappears, overtaken by extended upper branch. High-Reynolds VIV enters into the 2P domain in the Williamson–Roshko (W–R) map beginning with the initial branch. Hysteresis is not observed in these experiments possibly because parameters remain in the 2P-domain. High Reynolds numbers have a stronger influence than mass ratio on A/D. High-damping high-Reynolds VIV amplitudes are double of those predicted by the modified Griffin plot by extrapolation.     

Value addition of paper coating grade kaolins by the removal of ultrafine coloring impurities

Two kaolin samples from the southern part of Kerala (A and B) have been characterised. The colouring impurities present were found to be carbonaceous and ferruginous, being also present in ultrafine size ranges. Modern beneficiation techniques such as ultra flotation and high gradient magnetic separation (HGMS) have been carried out to reduce the level of these contaminants and to increase the brightness of the product clays. The results showed that nearly 70% of the ultrafine carbonaceous matter in A, which originally contains 0.13% carbon (as fixed carbon), could be removed by shear floc-flotation. HGMS treatment could remove ∼ 45% of the iron minerals (feed assay 0.58% Fe₂O₃). Sample B contained 0.32% Fe₂O₃ and 0.19% carbon. The shear floc-flotation was found to be the only effective method by which ∼ 75% of the carbon could be floated out. This sample did not respond to HGMS which may be because of the ‘structural’ nature of the iron present. Both the kaolins, after processing, were found suitable for paper coating. Another important aspect of this work is the establishment of maximum permissible level for carbon in paper coating grade clays since the standard specifications do not give any limiting value.     

Assessment of CMIP5 historical simulations of rainfall over Southeast Asia

Theoretical and Applied Climatology - We present preliminary analyses of the historical (1986–2005) climate simulations of a ten-member subset of the Coupled Model Inter-comparison Project...     

Regional climate simulations over Vietnam using the WRF model

Time-irreversible symmetry is a fundamental property of nonlinear time series. Time-irreversible behaviors of mean temperature measured on 182 stations over China from 1960 to 2012 are analyzed by directed horizontal visibility graph (DHVG for short), and significance of results has been estimated by Monte Carlo simulations. It is found that dominated time irreversibility emerges in nearly all daily temperature anomaly variations over China. Further studies indicate that these time-irreversible behaviors result from asymmetric distributions of persistent daily temperature increments and decrements, and this kind of symmetry can be quantified by distributions of consecutive daily mean temperature increasing or decreasing steps. At the same time, the findings above have been confirmed by artificially generated time series with given value of multiscale asymmetry.