Monthly Archives: November 2013

A forecasting model for short-term drinking water demand

Bakker, M., Vreeburg, J.H.G., van Schagen, K.M., Rietveld, L.C. A fully adaptive forecasting model for short-term drinking water demand. Environmental Modelling and Software. Oct2013, Vol. 48, p141-151.

For the optimal control of a water supply system, a short-term water demand forecast is necessary. We developed a model that forecasts the water demand for the next 48 h with 15-min time steps. The model uses measured water demands and static calendar data as single input. Based on this input, the model fully adaptively derives day factors and daily demand patterns for the seven days of the week, and for a configurable number of deviant day types. Although not using weather data as input, the model is able to identify occasional extra water demand in the evening during fair weather periods, and to adjust the forecast accordingly. The model was tested on datasets containing six years of water demand data in six different areas in the central and Southern part of Netherlands. The areas have all the same moderate weather conditions, and vary in size from very large (950,000 inhabitants) to small (2400 inhabitants). The mean absolute percentage error (MAPE) for the 24-h forecasts varied between 1.44 and 5.12%, and for the 15-min time step forecasts between 3.35 and 10.44%. The model is easy to implement, fully adaptive and accurate, which makes it suitable for application in real time control.

pharmaceutically active compounds (PhACs) in wastewater and sludge from wastewater treatment plants in Chongqing, China

Qing Yan, You-Peng Chen, Xu-Ya Peng, Yi-Xin Zhang, Xiu-Mei Gan, Cheng-Fang Zi, Jin-Song Guo. Occurrence, fate and ecotoxicological assessment of pharmaceutically active compounds in wastewater and sludge from wastewater treatment plants in Chongqing, the Three Gorges Reservoir Area. Science of The Total Environment, Volumes 470–471, 1 February 2014, Pages 618–630.

The occurrence, removal and ecotoxicological assessment of 21 pharmaceutically active compounds (PhACs) including antibiotics, analgesics, antiepileptics, antilipidemics and antihypersensitives, were studied at four municipal wastewater treatment plants (WWTP) in Chongqing, the Three Gorges Reservoir Area. Individual treatment unit effluents, as well as primary and secondary sludge, were sampled and analyzed for the selected PhACs to evaluate their biodegradation, persistence and partitioning behaviors. PhACs were identified and quantified using high performance liquid chromatography/tandem mass spectrometry after solid-phase extraction. All the 21 analyzed PhACs were detected in wastewater and the target PhACs except acetaminophen, ibuprofen and gemfibrozil, were also found in sludge. The concentrations of the antibiotics and SVT were comparable to or even higher than those reported in developed countries, while the case of other target PhACs was opposite. The elimination of PhACs except acetaminophen was incomplete and a wide range of elimination efficiencies during the treatment were observed, i.e. from “negative removal” to 99.5%. The removal of PhACs was insignificant in primary and disinfection processes, and was mainly achieved during the biological treatment. Based on the mass balance analysis, biodegradation is believed to be the primary removal mechanism, whereas only about 1.5% of the total mass load of the target PhACs was removed by sorption. Experimentally estimated distribution coefficients (< 500 L/kg, with a few exceptions) also indicate that biodegradation/transformation was responsible for the removal of the target PhACs. Ecotoxicological assessment indicated that the environment concentrations of single compounds (including sulfadiazine, sulfamethoxazole, ofloxacin, azithromycin and erythromycin-H2O) in effluent and sludge, as well as the mixture of the 21 detected PhACs in effluent, sludge and receiving water had a significant ecotoxicological risk to algae. Therefore, further control of PhACs in effluent and sludge is required before their discharge and application to prevent their introduction into the environment.

Click here for full paper (fee).

Gov. Chris Christy….a man for all liberals

Keeping the poor dependent upon government seems to be what liberalism and the democrat party are all about. Gov. Christy is doing his part for the liberal (establishment GOP?) cause in New Jersey. (click here)

happy bouncing smilie

Volcanic activity not the sole-cause of warming pause

Jim M. Haywood, Andy Jones, Gareth S. Jones. The impact of volcanic eruptions in the period 2000–2013 on global mean temperature trends evaluated in the HadGEM2-ES climate model. Atmospheric Science Letters. DOI: 10.1002/asl2.471

The slow-down in global warming over the last decade has lead to significant debate about whether the causes are of natural or anthropogenic origin. Using an ensemble of HadGEM2-ES coupled climate model simulations we investigate the impact of overlooked modest volcanic eruptions. We deduce a global mean cooling of around −0.02 to −0.03 K over the period 2008–2012. Thus while these eruptions do cause a cooling of the Earth and may therefore contribute to the slow-down in global warming, they do not appear to be the sole or primary cause.

Click here to obtain paper (fee).

How do IPCC models account for volcanic activity?

It is well-known that volcanic eruptions can spew large quantities of gases (even greenhouse gases), ash, and particulate matter into the atmosphere in quantities that dwarf other emission sources. Continuing large eruptions place a huge amount of particulate matter into the atmosphere. This particle matter reflects sunlight away from earth. When the particulate matter concentration is high enough, temperatures can drop.

Recently, 7 volcanoes erupted in six countries within a short period of time (click here).

My question? How do IPCC models account for effects of volcanic eruptions? If they do not, and I do not believe they can, then how can any of their projections into the future be realistic?

Marauding Muslims in Central Africa Republic attack Christians

“The Central African Republic (CAR) is “descending  into complete chaos,” becoming a breeding ground for extremists and  threatening to sink into religious and ethnic conflict that could spread  through an already troubled region, the U.N. Security Council was told  on Monday.” (click here)

Soon coming to a country near you (France, Europe, Great Britan, and the United States)?

Mr. Mitch McConnell, mind your own business, let Nebraska mind theirs

“After the Senate Conservative Fund (SCF) endorsed Matt Bevin, the Tea Party challenger to Senate Minority Leader Mitch McConnell (R-KY), McConnell has reportedly gone on a rampage against SCF allies and the conservative candidates it has endorsed.” Click here

If I lived in Nebraska, I’d say that its Mr. McConnell who deserves a punch in the nose, just as McConnell himself has threatened to do to others (click here).