On the meaning of feedback parameter, transient climate response, and the greenhouse effect: Basic considerations and the discussion of uncertainties

In this paper we discuss the meaning of feedback parameter, greenhouse effect and transient climate response usually related to the globally averaged energy balance model of Schneider and Mass. After scrutinizing this model and the corresponding planetary radiation balance we state that (a) the this globally averaged energy balance model is flawed by unsuitable physical considerations, (b) the planetary radiation balance for an Earth in the absence of an atmosphere is fraught by the inappropriate assumption of a uniform surface temperature, the so-called radiative equilibrium temperature of about 255 K, and (c) the effect of the radiative anthropogenic forcing, considered as a perturbation to the natural system, is much smaller than the uncertainty involved in the solution of the model of Schneider and Mass. This uncertainty is mainly related to the empirical constants suggested by various authors and used for predicting the emission of infrared radiation by the Earth's skin. Furthermore, after inserting the absorption of solar radiation by atmospheric constituents and the exchange of sensible and latent heat between the Earth and the atmosphere into the model of Schneider and Mass the surface temperatures become appreciably lesser than the radiative equilibrium temperature. Moreover, neither the model of Schneider and Mass nor the Dines-type two-layer energy balance model for the Earth-atmosphere system, both contain the planetary radiation balance for an Earth in the absence of an atmosphere as an asymptotic solution, do not provide evidence for the existence of the so-called atmospheric greenhouse effect if realistic empirical data are used.Comment: 69 pages, 3 tables and 16 figure

Similarity hypotheses for the atmospheric surface layer expressed by non-dimensional characteristic invariants - a review

In this paper, similarity hypotheses for the atmospheric surface layer (ASL) are reviewed using nondimensional characteristic invariants, referred to as π -numbers. The basic idea of this dimensional π-invariants analysis (sometimes also called Buckingham’s π-theorem) is described in a mathematically generalized formalism. To illustrate the task of this powerful method and how it can be applied to deduce a variety of reasonable solutions by the formalized procedure of non-dimensionalization, various instances are represented that are relevant to the turbulence transfer across the ASL and prevailing structure of ASL turbulence. Within the framework of our review we consider both (a) Monin-Obukhov scaling for forced-convective conditions, and (b) Prandtl-Obukhov-Priestley scaling for free-convective conditions.It is shown that in the various instances of Monin-Obukhov scaling generally two π-numbers occur that result in corresponding similarity functions. In contrast to that, Prandtl-Obukhov-Priestley scaling will lead to only one π number in each case usually considered as a non-dimensional universal constant. Since an explicit mathematical relationship for the similarity functions cannot be obtained from a dimensional π-invariants analysis, elementary laws of π-invariants have to be pointed out using empirical or/and theoretical findings. To evaluate empirical similarity functions usually considered within the framework flux-profile relationships, so-called integral similarity functions for momentum and sensible heat are presented and assessed on the basis of the friction velocity and the vertical component of the eddy flux densities of sensible and latent heat directly measured during the GREIV I 1974 field campaign

Catheter-Associated Urinary Tract Infection Reduction: A Quality Improvement Project

Abstract Problem: Hospital-acquired infections are preventable harm that occurs to patients while in the hospital. Catheter-associated urinary tract infection (CAUTI) is a preventable hospital-acquired infection that continues to plague hospitals nationwide. The Centers for Disease Control and Prevention estimates that there are more than 13,000 CAUTI related deaths in the United States annually (Scanlon, 2017). In addition to the harm caused to patients by CAUTIs, the estimated $500 million yearly cost for CAUTI treatment has created a fiscal burden on healthcare systems (Scanlon, 2017). Decreasing the rate of CAUTI by decreasing overall number of catheters is the goal of this performance improvement project. Context: Within a large northern California healthcare system, at one Santa Clara, California hospital, the medical neurology unit, Department 430, is an inpatient hospital unit that provides care to a diverse patient population. This unit had 7 CAUTIs in 2017, which was the most of any unit within this hospital. A strengths, weaknesses, opportunities, and threats analysis of the unit revealed there was no daily process in which catheter necessity was discussed between the multidisciplinary team. This unit was also identified to have more catheter line days than expected by the National Healthcare Safety Network. Intervention: The main intervention of this performance improvement project is a daily catheter rounding team, which consists of a nurse quality consultant, physician lead, department nursing leader, and infection control nurse. The rounding team reviews catheter patients daily and discusses catheter removal in real time. The catheter rounding team is expected to decrease the overall number of line days and, therefore, decrease infection rates. Measures: During project development, a family of measures was identified to help track project goals and to identify if the project made a change. The specific outcome measures for this project will be a 30% reduction in catheter line days and a 30% reduction in the unit’s CAUTI rate per 1,000-line days from the project initiation. The two process measures that will evaluate the success of the project’s outcome metric are number of catheters removed during rounds and the percent of patients who have a catheter correctly placed using the bladder scanning protocol. A balancing measure of patient falls will also be tracked to ensure that there is no correlation between catheter removal and patients falling when using the toilet. Results: After implementation of the main intervention of the catheter rounding team, the unit saw an overall decrease in line days by 31.4% from the same period the previous year. In addition to line day reduction, the CAUTI rate per 1,000-line days decrease by 36.4% from the start of the project. Conclusions: The introduction of the catheter rounding team was successful at decreasing the overall number of line days, as well as the CAUTI rate. The introduction of tools for the frontline staff to utilize when making decisions to contact the physicians regarding line necessity were suspected of spreading an increased overall awareness of daily catheter necessity evaluation. Without full-time equivalents to continue the rounding team, the unit leadership and physician lead will be crucial in the sustainability of the unit’s CAUTI reduction success. In conclusion, the implications for practice based on this project include the introduction of a catheter rounding team to increase awareness of catheters that are in place, decrease the overall catheter line days and CAUTI rate, and reduce unnecessary harm to patients