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Lars Ribbe

Bio: Lars Ribbe is an academic researcher from Cologne University of Applied Sciences. The author has contributed to research in topics: Water resources & Drainage basin. The author has an hindex of 22, co-authored 81 publications receiving 1447 citations. Previous affiliations of Lars Ribbe include University of Cologne & ITT Technical Institute.


Papers
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Journal ArticleDOI
TL;DR: This study found that expansion of cultivation land and decline in woody shrub/woodland appear to be major environmental stressors affecting local water resources, especially in relation to erosion and sedimentation in the upper Blue Nile River Basin.

200 citations

Journal ArticleDOI
TL;DR: In this paper, the suitability of seven state-of-the-art SRE products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIAN-CCS-Adj, MSWEPv1.1, and PGFv3) over the complex topography and diverse climatic gradients of Chile was exhaustively evaluated.
Abstract: . Accurate representation of the real spatio-temporal variability of catchment rainfall inputs is currently severely limited. Moreover, spatially interpolated catchment precipitation is subject to large uncertainties, particularly in developing countries and regions which are difficult to access. Recently, satellite-based rainfall estimates (SREs) provide an unprecedented opportunity for a wide range of hydrological applications, from water resources modelling to monitoring of extreme events such as droughts and floods. This study attempts to exhaustively evaluate – for the first time – the suitability of seven state-of-the-art SRE products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIANN-CDR, PERSIAN-CCS-Adj, MSWEPv1.1, and PGFv3) over the complex topography and diverse climatic gradients of Chile. Different temporal scales (daily, monthly, seasonal, annual) are used in a point-to-pixel comparison between precipitation time series measured at 366 stations (from sea level to 4600 m a.s.l. in the Andean Plateau) and the corresponding grid cell of each SRE (rescaled to a 0.25° grid if necessary). The modified Kling–Gupta efficiency was used to identify possible sources of systematic errors in each SRE. In addition, five categorical indices (PC, POD, FAR, ETS, fBIAS) were used to assess the ability of each SRE to correctly identify different precipitation intensities. Results revealed that most SRE products performed better for the humid South (36.4–43.7° S) and Central Chile (32.18–36.4° S), in particular at low- and mid-elevation zones (0–1000 m a.s.l.) compared to the arid northern regions and the Far South. Seasonally, all products performed best during the wet seasons (autumn and winter; MAM–JJA) compared to summer (DJF) and spring (SON). In addition, all SREs were able to correctly identify the occurrence of no-rain events, but they presented a low skill in classifying precipitation intensities during rainy days. Overall, PGFv3 exhibited the best performance everywhere and for all timescales, which can be clearly attributed to its bias-correction procedure using 217 stations from Chile. Good results were also obtained by the research products CHIRPSv2, TMPA 3B42v7 and MSWEPv1.1, while CMORPH, PERSIANN-CDR, and the real-time PERSIANN-CCS-Adj were less skillful in representing observed rainfall. While PGFv3 (currently available up to 2010) might be used in Chile for historical analyses and calibration of hydrological models, the high spatial resolution, low latency and long data records of CHIRPS and TMPA 3B42v7 (in transition to IMERG) show promising potential to be used in meteorological studies and water resource assessments. We finally conclude that despite improvements of most SRE products, a site-specific assessment is still needed before any use in catchment-scale hydrological studies.

192 citations

Journal ArticleDOI
TL;DR: The Random Forest based MErging Procedure (RF-MEP), which combines information from ground-based measurements, state-of-the-art precipitation products, and topography-related features to improve the representation of the spatio-temporal distribution of precipitation, is presented, especially in data-scarce regions.

119 citations

Journal ArticleDOI
TL;DR: In this article, the authors evaluate disaster risk perception (DRP) and intervention measures of the population living in flood risk areas and relate it to variables such as landslide risk perception, experienced disasters, taken from institutions and the population.
Abstract: The flooding and landslides catastrophe in 2011 in the mountainous area of Rio de Janeiro State in Brazil affected more than 300,000 people and created unquantifiable material losses, mostly in the Nova Friburgo Municipality. Even with the available technologies, programs and measures for disaster prevention, the population was not prepared. Following international frameworks like the Hyogo, governmental institutions related to risk management started working with the population to improve response, preparedness and perception. This work aims to evaluate disaster risk perception (DRP) and intervention measures of the population living in flood risk areas and relate it to variables such as landslide risk perception, experienced disasters and intervention measures taken from institutions and the population. Through 391 quantitative questionnaires and 20 semi-structured qualitative interviews, we reveal the connection between DRP, the people who may be affected and the strategies for response and preparedness of the institutions. Using descriptive statistics, factor analysis and regression, we develop six main factors related to risk perception. The regression defines flood risk perception (FRP) as the dependent factor and exposes the small influence on FRP from state and municipal institutions working with disaster risk reduction (~ 0.01) in comparison to past experiences (~ 0.52), demographic characteristics (~ 0.29) and local influences (~ 0.62). Supporting literature about DRP, examples about institutional influences are given. Hard and soft intervention measures exemplify neighborhoods developing perceptions according to institutional influences, local organization strategies and marginalization level, highlighting the importance of local participation on risk reduction programs to improve perception, trust and therefore, intervention measures.

78 citations

Journal ArticleDOI
TL;DR: The results show that theEconomic gain of the Blue Nile Basin from WEF increases with raising the cooperation level between Ethiopia and Sudan to collaboration, however, the economic gain of each riparian country does not necessarily follow the same pattern as the economic loss of the basin.

75 citations


Cited by
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Journal ArticleDOI
TL;DR: A forum to review, analyze and stimulate the development, testing and implementation of mitigation and adaptation strategies at regional, national and global scales as mentioned in this paper, which contributes to real-time policy analysis and development as national and international policies and agreements are discussed.
Abstract: ▶ Addresses a wide range of timely environment, economic and energy topics ▶ A forum to review, analyze and stimulate the development, testing and implementation of mitigation and adaptation strategies at regional, national and global scales ▶ Contributes to real-time policy analysis and development as national and international policies and agreements are discussed and promulgated ▶ 94% of authors who answered a survey reported that they would definitely publish or probably publish in the journal again

2,587 citations

01 Dec 2010
TL;DR: In this article, the authors suggest a reduction in the global NPP of 0.55 petagrams of carbon, which would not only weaken the terrestrial carbon sink, but would also intensify future competition between food demand and biofuel production.
Abstract: Terrestrial net primary production (NPP) quantifies the amount of atmospheric carbon fixed by plants and accumulated as biomass. Previous studies have shown that climate constraints were relaxing with increasing temperature and solar radiation, allowing an upward trend in NPP from 1982 through 1999. The past decade (2000 to 2009) has been the warmest since instrumental measurements began, which could imply continued increases in NPP; however, our estimates suggest a reduction in the global NPP of 0.55 petagrams of carbon. Large-scale droughts have reduced regional NPP, and a drying trend in the Southern Hemisphere has decreased NPP in that area, counteracting the increased NPP over the Northern Hemisphere. A continued decline in NPP would not only weaken the terrestrial carbon sink, but it would also intensify future competition between food demand and proposed biofuel production.

1,780 citations

Journal Article
TL;DR: 1. Place animal in induction chamber and anesthetize the mouse and ensure sedation, move it to a nose cone for hair removal using cream and reduce anesthesia to maintain proper heart rate.
Abstract: 1. Place animal in induction chamber and anesthetize the mouse and ensure sedation. 2. Once the animal is sedated, move it to a nose cone for hair removal using cream. Only apply cream to the area of the chest that will be utilized for imaging. Once the hair is removed, wipe area with wet gauze to ensure all hair is removed. 3. Move the animal to the imaging platform and tape its paws to the ECG lead plates and insert rectal probe. Body temperature should be maintained at 36-37°C. During imaging, reduce anesthesia to maintain proper heart rate. If the animal shows signs of being awake, use a higher concentration of anesthetic.

1,557 citations

Journal ArticleDOI
TL;DR: A copy of the Guangbo jiemu bao [Broadcast Program Report] was being passed from hand to hand among a group of young people eager to be the first to read the article introducing the program "What Is Revolutionary Love?".
Abstract: A copy of Guangbo jiemu bao [Broadcast Program Report] was being passed from hand to hand among a group of young people eager to be the first to read the article introducing the program "What Is Revolutionary Love?" It said: "… Young friends, you are certainly very concerned about this problem'. So, we would like you to meet the young women workers Meng Xiaoyu and Meng Yamei and the older cadre Miss Feng. They are the three leading characters in the short story ‘The Place of Love.’ Through the description of the love lives of these three, the story induces us to think deeply about two questions that merit further examination.

1,528 citations

Book
01 Jan 2005

620 citations