The potential of urban rainfall monitoring with crowdsourced automatic weather stations in Amsterdam

Abstract. The high density of built-up areas and resulting imperviousness of the land surface makes urban areas vulnerable to extreme rainfall, which can lead to considerable damage. In order to design and manage cities to be able to deal with the growing number of extreme rainfall events, rainfall data is required at higher temporal and spatial resolutions than those needed for rural catchments. However, the density of operational rainfall monitoring networks managed by local or national authorities is typically low in urban areas. A growing number of automatic personal weather stations (PWSs) link rainfall measurements to online platforms. Here, we examine the potential of such crowdsourced datasets for obtaining the desired resolution and quality of rainfall measurements for the capital of the Netherlands. Data from 63 stations in Amsterdam (~ 575 km2) that measure rainfall over at least 4 months in a 17-month period are evaluated, in addition to a detailed assessment that is made of three Netatmo stations, the largest contributor of the dataset, in an experimental set-up. Although the sensor performance in the experimental set-up and the density of the PWS-network are promising, the method of data transfer to the online platform causes considerable errors in the datasets obtained. These errors are especially large during low intensity rainfall, although they can be reduced by accumulating rainfall over longer intervals, improving the correlation with gauge-adjusted radar data from 0.48 at 5 min intervals to 0.60 at hourly intervals. Spatial rainfall correlation functions derived from PWS data show much more small-scale variability than those based on gauge-adjusted radar data and those found in similar research using dedicated rain gauge networks. This can largely be attributed to the noise in the PWS data resulting from both the measurement setup and the data conversion by the PWS-platform. A double mass comparison with gauge-adjusted radar data shows that the median of the stations resembles the rainfall reference better than the real-time available (unadjusted) radar product. Averaging nearby raw PWS measurements already improves the match with gauge-adjusted radar data in that area. The results confirm that the growing number of internet-connected PWSs holds a promise for urban rainfall monitoring.

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The potential of urban rainfall monitoring with crowdsourced automatic weather stations in Amsterdam

Hydrology and Earth System Sciences ◽

10.5194/hess-21-765-2017 ◽

2017 ◽

Vol 21 (2) ◽

pp. 765-777 ◽

Cited By ~ 32

Author(s):

Lotte de Vos ◽

Hidde Leijnse ◽

Aart Overeem ◽

Remko Uijlenhoet

Keyword(s):

Land Surface ◽

Urban Areas ◽

Extreme Rainfall ◽

Radar Data ◽

Rain Gauge ◽

Small Scale ◽

Experimental Setup ◽

Monitoring Networks ◽

Online Platforms ◽

Weather Stations

Abstract. The high density of built-up areas and resulting imperviousness of the land surface makes urban areas vulnerable to extreme rainfall, which can lead to considerable damage. In order to design and manage cities to be able to deal with the growing number of extreme rainfall events, rainfall data are required at higher temporal and spatial resolutions than those needed for rural catchments. However, the density of operational rainfall monitoring networks managed by local or national authorities is typically low in urban areas. A growing number of automatic personal weather stations (PWSs) link rainfall measurements to online platforms. Here, we examine the potential of such crowdsourced datasets for obtaining the desired resolution and quality of rainfall measurements for the capital of the Netherlands. Data from 63 stations in Amsterdam (∼ 575 km2) that measure rainfall over at least 4 months in a 17-month period are evaluated. In addition, a detailed assessment is made of three Netatmo stations, the largest contributor to this dataset, in an experimental setup. The sensor performance in the experimental setup and the density of the PWS network are promising. However, features in the online platforms, like rounding and thresholds, cause changes from the original time series, resulting in considerable errors in the datasets obtained. These errors are especially large during low-intensity rainfall, although they can be reduced by accumulating rainfall over longer intervals. Accumulation improves the correlation coefficient with gauge-adjusted radar data from 0.48 at 5 min intervals to 0.60 at hourly intervals. Spatial rainfall correlation functions derived from PWS data show much more small-scale variability than those based on gauge-adjusted radar data and those found in similar research using dedicated rain gauge networks. This can largely be attributed to the noise in the PWS data resulting from both the measurement setup and the processes occurring in the data transfer to the online PWS platform. A double mass comparison with gauge-adjusted radar data shows that the median of the stations resembles the rainfall reference better than the real-time (unadjusted) radar product. Averaging nearby raw PWS measurements further improves the match with gauge-adjusted radar data in that area. These results confirm that the growing number of internet-connected PWSs could successfully be used for urban rainfall monitoring.

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Utilising Citizen Science Rain Data for Improved Rainfall Estimation in Urban Pluvial Flooding

10.5194/egusphere-egu21-8734 ◽

2021 ◽

Author(s):

Tess O'Hara ◽

Geoff Parkin ◽

Hayley Fowler ◽

Elizabeth Lewis ◽

Fergus McClean ◽

...

Keyword(s):

Citizen Science ◽

Urban Areas ◽

Monitoring Network ◽

Extreme Rainfall ◽

Rain Gauge ◽

Poor Quality ◽

High Resolution Data ◽

Pluvial Flooding ◽

Weather Stations ◽

Rain Data

Did you know there are millions of rain observations from thousands of privately owned automated weather stations located throughout Britain (and beyond) held in a freely accessible online archive? Citizen Scientists are sharing detailed sub-daily weather observations, including from locations where other gauge data is not available, often in close to real-time. There is distinct clustering of rain gauges in British urban areas, and with an anticipated increase in convective storms resulting in localised pluvial flooding, such high-resolution data should not be ignored. The aims of this research are to assess data quality, investigate how access to the data can be made easier, and to explore how the data can be used to support improved flood risk assessment.British rain observations are presented, spanning 10 years from more than 3000 unique citizen science weather stations via the Met Office WOW archive. These citizen science observations have the potential to fill gaps in the official monitoring network run by the Met Office and agencies responsible for flooding in Britain. Analysis indicates that if the official ground based rain gauge network was interpolated on a 5km grid there would be coverage for 36% of Britain, but if citizen science weather stations were included that figure increases to over 50%. A methodology to identify poor quality observations has been developed; the preliminary findings show that even where absolute values may be inaccurate, citizen science gauges can capture the pattern of extreme rainfall. Examples are shown from work in progress showing how combining citizen science observations with official rain data (radar and ground based gauges) can improve delineation of specific events that resulted in pluvial flooding.

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A New Land Surface Hydrology within the Noah-WRF Land-Atmosphere Mesoscale Model Applied to Semiarid Environment: Evaluation over the Dantiandou Kori (Niger)

Advances in Meteorology ◽

10.1155/2009/731874 ◽

2009 ◽

Vol 2009 ◽

pp. 1-13 ◽

Cited By ~ 8

Author(s):

B. Decharme ◽

C. Ottlé ◽

S. Saux-Picart ◽

N. Boulain ◽

B. Cappelaere ◽

...

Keyword(s):

Land Surface ◽

Mesoscale Model ◽

West African Monsoon ◽

Radar Data ◽

Rain Gauge ◽

Surface Energy Budget ◽

Surface Hydrology ◽

Land Surface Hydrology ◽

Rain Gauge Network

Land-atmosphere feedbacks, which are particularly important over the Sahel during the West African Monsoon (WAM), partly depend on a large range of processes linked to the land surface hydrology and the vegetation heterogeneities. This study focuses on the evaluation of a new land surface hydrology within the Noah-WRF land-atmosphere-coupled mesoscale model over the Sahel. This new hydrology explicitly takes account for the Dunne runoff using topographic information, the Horton runoff using a Green-Ampt approximation, and land surface heterogeneities. The previous and new versions of Noah-WRF are compared against a unique observation dataset located over the Dantiandou Kori (Niger). This dataset includes dense rain gauge network, surfaces temperatures estimated from MSG/SEVIRI data, surface soil moisture mapping based on ASAR/ENVISAT C-band radar data and in situ observations of surface atmospheric and land surface energy budget variables. Generally, the WAM is reasonably reproduced by Noah-WRF even if some limitations appear throughout the comparison between simulations and observations. An appreciable improvement of the model results is also found when the new hydrology is used. This fact seems to emphasize the relative importance of the representation of the land surface hydrological processes on the WAM simulated by Noah-WRF over the Sahel.

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Extreme Rainfall Events in the Macro-Metropolis of São Paulo: trends and connection with climate oscillations

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-20-0173.1 ◽

2021 ◽

Author(s):

Carolyne B. Machado ◽

Thamiris L. O. B. Campos ◽

Sameh A. Abou Rafee ◽

Jorge A. Martins ◽

Alice M. Grimm ◽

...

Keyword(s):

Urban Areas ◽

Extreme Rainfall ◽

Kendall Test ◽

Rain Gauge ◽

Sao Paulo ◽

Annual Rainfall ◽

São Paulo ◽

Wet Season ◽

Extreme Rainfall Events ◽

Climatic Indices

AbstractIn the present work, the trend of extreme rainfall indices in the Macro-Metropolis of São Paulo (MMSP) was analyzed and correlated with largescale climatic oscillations. A cluster analysis divided a set of rain gauge stations into three homogeneous regions within MMSP, according to the annual cycle of rainfall. The entire MMSP presented an increase in the total annual rainfall, from 1940 to 2016, of 3 mm per year on average, according to Mann-Kendall test. However, there is evidence that the more urbanized areas have a greater increase in the frequency and magnitude of extreme events, while coastal and mountainous areas, and regions outside large urban areas, have increasing rainfall in a better-distributed way throughout the year. The evolution of extreme rainfall (95th percentile) is significantly correlated with climatic indices. In the center-north part of the MMSP, the combination of Pacific Decadal Oscillation (PDO) and Antarctic Oscillation (AAO) explains 45% of the P95th increase during the wet season. In turn, in southern MMSP, the Temperature of South Atlantic (TSA), the AAO, the El Niño South Oscillation (ENSO) and the Multidecadal Oscillation of the North Atlantic (AMO) better explain the increase in extreme rainfall (R2 = 0.47). However, the same is not observed during the dry season, in which the P95th variation was only negatively correlated with the AMO, undergoing a decrease from the ‘70s until the beginning of this century. The occurrence of rainy anomalous months proved to be more frequent and associated with climatic indices than dry months.

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Under the ice and over the sky – aspects of building the International Quaternary Map of Europe and potentially useful parallels to planetary geological map projects

10.5194/egusphere-egu2020-22610 ◽

2020 ◽

Author(s):

Kristine Asch ◽

Andrea Naß ◽

Stephan van Gasselt

Keyword(s):

Land Surface ◽

Active Faults ◽

Geological Mapping ◽

Geographical Information ◽

Current Status ◽

Small Scale ◽

Scientific Quality ◽

European Continent ◽

Geological Map ◽

Set Up

The project of the International Quaternary Map of Europe project (IQUAME 2500) is a major international initiative coordinated by BGR under the auspices of the CGMW (Commission of the Geological Map of the Word, Sub-Commission Europe) and with support of INQUA (International Union for Quaternary Research). It started in 2011 at the INQUA congress in Bern and aims to show the distribution of Quaternary features at the land surface and general marine deposits across the entire European continent. The map is planned as web-based geographical information system (GIS) and is going to include the Quaternary on- and off-shore information on e.g. glaciogenic elements, geomorphologic features, age and lithology of Quaternary units, last extent of ice sheets (Weichselian, Saalian, if possible Elsterian), faults, active faults off-shore Quaternary information (in cooperation with the European Union EMODnet Geology project) and more.Partner institutions from more than 30 countries including geological survey organisations from Russia in the East, Portugal in the West, Norway in the North and Cyprus in the South are participating; a scientific board of Quaternary researchers ensures the high scientific quality of resulting map. For a multinational and cross-boundary project like this, international collaboration is the key to success. This project requires that data originally set up in a plethora of regional and national classifications need to be adapted, integrated and harmonized in respect to semantics, structure and geometry. To achieve this aim common rules needed to used such as those defined by the European INSPIRE Directive or be set up and applied by all participants:&#160; structured vocabularies (incl. definitions of terms) to describe the above contents, cartographic guidelines to suite the scale and last but not least generally applicable tools to aid the partners to submit their data to the project.Ultimately, the aim is to create an pan-European, internationally harmonized, comprehensive, spatial geological database where relevant properties of the Quaternary layers can be retrieved, combined, selected and cross-referenced across political boundaries and also to provide a summary of the current status of European Quaternary geological research.Looking at planetary mapping, e.g. of Mars and Moon, there are several similarities. The surfaces of terrestrial planets are shaped by geologic processes that are similar to those operating on Earth, therefore endogenic and exogenic landforms (such as lava flows, glacial deposits, and impact craters) are regularly mapped by the scientific community. &#160;Beside specific scientific mapping projects conducted by individual researchers and groups different organisations and institutes are producing planetary maps, such as NASA, ESA, ROSCOSMOS and MIIGAiK (Russia), USGS (USA), CAS/NOAC/SGCAS/RADI (China), DLR (Germany), or the British Ordnance Survey. This presentation aims to introduce the small-scale Quaternary mapping of one part of planet Earth, i.e. Europe, to present its collaborative aspects, to highlight the parallels to planetary mapping and to suggest potentially useful aspects for planetary geological mapping projects.

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Statistical Characteristic of Heavy Rainfall Associated with Typhoons near Taiwan Based on High-Density Automatic Rain Gauge Data

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-15-00076.1 ◽

2016 ◽

Vol 97 (8) ◽

pp. 1363-1375 ◽

Cited By ~ 9

Author(s):

Chun-Chieh Wu ◽

Tzu-Hsiung Yen ◽

Yi-Hsuan Huang ◽

Cheng-Ku Yu ◽

Shin-Gan Chen

Keyword(s):

Heavy Rainfall ◽

Extreme Rainfall ◽

Rain Gauge ◽

Statistical Characteristics ◽

Rain Gauge Data ◽

Mountainous Regions ◽

Rain Gauges ◽

Weather Stations ◽

Central Weather Bureau

Abstract This study utilizes data compiled over 21 years (1993–2013) from the Central Weather Bureau of Taiwan to investigate the statistical characteristics of typhoon-induced rainfall for 53 typhoons that have impacted Taiwan. In this work the data are grouped into two datasets: one includes 21 selected conventional weather stations (referred to as Con-ST), and the other contains all the available rain gauges (250–500 gauges, mostly automatic ones; referred to as All-ST). The primary aim of this study is to understand the potential impacts of the different gauge distributions between All-ST and Con-ST on the statistical characteristics of typhoon-induced rainfall. The analyses indicate that although the average rainfall amount calculated with Con-ST is statistically similar to that with All-ST, the former cannot identify the precipitation extremes and rainfall distribution appropriately, especially in mountainous areas. Because very few conventional stations are located over the mountainous regions, the cumulative frequency obtained solely from Con-ST is not representative. As compared to the results from All-ST, the extreme rainfall assessed from Con-ST is, on average, underestimated by 23%–44% for typhoons approaching different portions of Taiwan. The uneven distribution of Con-ST, with only three stations located in the mountains higher than 1000 m, is likely to cause significant biases in the interpretation of rainfall patterns. This study illustrates the importance of the increase in the number of available stations in assessing the long-term rainfall characteristic of typhoon-associated heavy rainfall in Taiwan.

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Gauge-adjusted rainfall estimates from commercial microwave links

Hydrology and Earth System Sciences ◽

10.5194/hess-21-617-2017 ◽

2017 ◽

Vol 21 (1) ◽

pp. 617-634 ◽

Cited By ~ 15

Author(s):

Martin Fencl ◽

Michal Dohnal ◽

Jörg Rieckermann ◽

Vojtěch Bareš

Keyword(s):

Urban Areas ◽

Ground Truth ◽

Telecommunication Networks ◽

Monitoring Networks ◽

Mobile Telecommunication ◽

Rain Gauges ◽

Precipitation Estimates ◽

Set Up ◽

Quantitative Precipitation Estimates ◽

Commercial Microwave Links

Abstract. Increasing urbanization makes it more and more important to have accurate stormwater runoff predictions, especially with potentially severe weather and climatic changes on the horizon. Such stormwater predictions in turn require reliable rainfall information. Especially for urban centres, the problem is that the spatial and temporal resolution of rainfall observations should be substantially higher than commonly provided by weather services with their standard rainfall monitoring networks. Commercial microwave links (CMLs) are non-traditional sensors, which have been proposed about a decade ago as a promising solution. CMLs are line-of-sight radio connections widely used by operators of mobile telecommunication networks. They are typically very dense in urban areas and can provide path-integrated rainfall observations at sub-minute resolution. Unfortunately, quantitative precipitation estimates (QPEs) from CMLs are often highly biased due to several epistemic uncertainties, which significantly limit their usability. In this manuscript we therefore suggest a novel method to reduce this bias by adjusting QPEs to existing rain gauges. The method has been specifically designed to produce reliable results even with comparably distant rain gauges or cumulative observations. This eliminates the need to install reference gauges and makes it possible to work with existing information. First, the method is tested on data from a dedicated experiment, where a CML has been specifically set up for rainfall monitoring experiments, as well as operational CMLs from an existing cellular network. Second, we assess the performance for several experimental layouts of ground truth from rain gauges (RGs) with different spatial and temporal resolutions. The results suggest that CMLs adjusted by RGs with a temporal aggregation of up to 1 h (i) provide precise high-resolution QPEs (relative error  < 7 %, Nash–Sutcliffe efficiency coefficient  >  0.75) and (ii) that the combination of both sensor types clearly outperforms each individual monitoring system. Unfortunately, adjusting CML observations to RGs with longer aggregation intervals of up to 24 h has drawbacks. Although it substantially reduces bias, it unfavourably smoothes out rainfall peaks of high intensities, which is undesirable for stormwater management. A similar, but less severe, effect occurs due to spatial averaging when CMLs are adjusted to remote RGs. Nevertheless, even here, adjusted CMLs perform better than RGs alone. Furthermore, we provide first evidence that the joint use of multiple CMLs together with RGs also reduces bias in their QPEs. In summary, we believe that our adjustment method has great potential to improve the space–time resolution of current urban rainfall monitoring networks. Nevertheless, future work should aim to better understand the reason for the observed systematic error in QPEs from CMLs.

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The Contribution of Orographically Driven Banded Precipitation to the Rainfall Climatology of a Mediterranean Region

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-10-05016.1 ◽

2011 ◽

Vol 50 (11) ◽

pp. 2235-2246 ◽

Cited By ~ 18

Author(s):

Angélique Godart ◽

Sandrine Anquetin ◽

Etienne Leblois ◽

Jean-Dominique Creutin

Keyword(s):

Deep Convection ◽

Regional Climate ◽

Extreme Rainfall ◽

Rain Gauge ◽

Western Mediterranean ◽

Small Scale ◽

Shallow Convection ◽

Extreme Rainfall Events ◽

Atmospheric Flow ◽

Rainfall Climatology

AbstractStudies carried out worldwide show that topography influences rainfall climatology. As in most western Mediterranean regions, the mountainous Cévennes–Vivarais area in France regularly experiences extreme precipitation that may lead to devastating flash floods. Global warming could further aggravate this situation, but this possibility cannot be confirmed without first improving the understanding of the role of topography in the regional climate and, in particular, for extreme rainfall events. This paper focuses on organized banded rainfall and evaluates its contribution to the rainfall climatology of this region. Stationary rainfall systems made up of such bands are triggered and enhanced by small-scale interactions between the atmospheric flow and the relief. Rainbands are associated with shallow convection and are also present in deep-convection events for specific flux directions. Such precipitation patterns are difficult to observe both with operational weather radar networks, which are not designed to observe low-level convection within complex terrain, and with rain gauge networks, for which gauge spacing is typically larger than the bandwidth. A weather class of banded orographic shallow-convection events is identified, and the contribution of such events to annual or seasonal precipitation over the region is assessed. Moreover, a method is also proposed to quantify the contribution of banded convection during specific deep-convection events. It is shown that even though these orographically driven banded precipitation events produce moderate precipitation intensities they have long durations and therefore represent a significant amount of the rainfall climatology of the region, producing up to 40% of long-term total precipitation at certain locations.

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Investigating vegetation role on UHI with mechanistic modelling worldwide

10.5194/egusphere-egu21-4198 ◽

2021 ◽

Author(s):

Ziyan Zhang ◽

Athanasios Paschalis ◽

Ana Mijic ◽

Naika Meili ◽

Simone Fatichi

Keyword(s):

Land Surface ◽

Urban Areas ◽

Energy Demand ◽

Land Surface Model ◽

Remote Sensing Data ◽

Global Scale ◽

Surface Model ◽

Urban Fabric ◽

Urban Energy ◽

Set Up

The urban heat island effect (UHI), defined as the temperature difference between urban areas and their surroundings, has been widely observed in many cities worldwide, impacting urban energy demand, citizen&#8217;s comfort and health. UHI intensities have been found to depend on background climate, and the urban fabric, including built (building thermal properties, heights, reflectance) and natural characteristics (vegetation cover, species composition, vegetation management). In this study, we focus on developing a global scale mechanistic understanding of how each of those properties alters the urban energy budget and leads to UHI development. To achieve this goal, we use the state-of-art urban ecohydrological and land-surface model (urban Tethys-Chloris) to perform a set of detailed UHI simulations for multiple large urban clusters across America, Europe and China in a 10-year time period (2009-2019), spanning a gradient of aridity, vegetation amount, and different compositions of the urban fabric. Model simulations were set up using the latest generation remote sensing data and climate reanalysis (ERA5). Using the simulations, we develop a paradigm of how UHIs develop worldwide, and propose viable solutions for sustainable UHI mitigation.

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Rainfall monitoring in Sri Lanka employing commercial microwave links

10.5194/egusphere-egu21-7793 ◽

2021 ◽

Author(s):

Aart Overeem ◽

Hidde Leijnse ◽

Thomas van Leth ◽

Linda Bogerd ◽

Jan Priebe ◽

...

Keyword(s):

Sri Lanka ◽

Land Surface ◽

Urban Areas ◽

Weather Prediction ◽

Rain Gauge ◽

Cellular Communication ◽

Dual Frequency ◽

Middle Income ◽

Rain Gauges ◽

Weather Radars

Microwave backhaul links from cellular communication networks provide a valuable &#8220;opportunistic&#8221; source of high-resolution space&#8211;time rainfall information, complementing traditional in situ measurement devices (rain gauges, disdrometers) and remote sensors (weather radars, satellites). Over the past decade, a growing community of researchers has, in close collaboration with cellular communication companies, developed retrieval algorithms to convert the raw microwave link signals, stored operationally by their network management systems, to hydrometeorologically useful rainfall estimates. Operational meteorological and hydrological services as well as private consulting firms are showing an increased interest in using this complementary source of rainfall information to improve the products and services they provide to end users from different sectors, from water management and weather prediction to agriculture and traffic control. The greatest potential of these opportunistic environmental sensors lies in those geographical areas over the land surface of the Earth with few rain gauges and no weather radars: often mountainous and urban areas, but especially low- to middle-income regions, which are generally in (sub)tropical climates.&#160;Here, the open-source R package RAINLINK is employed to retrieve CML rainfall maps covering the majority of Sri Lanka, a middle-income country having a tropical climate. This is performed for a 3.5-month period based on CML data from on average 1140 link paths. CML rainfall maps are compared locally to hourly and daily rain gauge data, as well as to rainfall maps from the Dual-frequency Precipitation Radar on board the Global Precipitation Measurement Core Observatory satellite. The results confirm the potential of CMLs for real-time tropical rainfall monitoring. This holds a promise for, e.g., ground validation of or merging with satellite precipitation products.

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