Articles | Volume 24, issue 9
Research article 21 Sep 2020
Research article | 21 Sep 2020
A universal Standardized Precipitation Index candidate distribution function for observations and simulations
Patrick Pieper et al.
No articles found.
Marcel Meyer, Iuliia Polkova, Kameswar Rao Modali, Laura Schaffer, Johanna Baehr, Stephan Olbrich, and Marc Rautenhaus
Weather Clim. Dynam. Discuss.,
Preprint under review for WCDShort summary
Novel techniques from computer science are used to study extreme weather events. Inspired by the interactive 3-dimensional visual analysis of the most comprehensive climatological dataset available (ERA5), we improve commonly used metrics for measuring polar winter storms and outbreaks of cold air. The software (Met.3D) that we develop and apply is freely available and can be used generically for visual analysis of a broad variety of atmospheric processes in weather and climate data.
Tim Rohrschneider, Johanna Baehr, Veit Lüschow, Dian Putrasahan, and Jochem Marotzke
Ocean Sci. Discuss.,
Preprint under review for OSShort summary
This paper presents an analysis of wind and warming sensitivity experiments in order to provide insight into the Atlantic inter-hemispheric circulation by understanding the behavior of the depth scale(s) of the AMOC. We put into question the common view that the AMOC is a nonlocal phenomenon only. The analysis of the wind experiments and the warming experiment suggests a hemisphere-dependent scaling of the strength of AMOC and temporal adjustment to global warming.
Hilla Afargan-Gerstman, Iuliia Polkova, Lukas Papritz, Paolo Ruggieri, Martin P. King, Panos J. Athanasiadis, Johanna Baehr, and Daniela I. V. Domeisen
Weather Clim. Dynam., 1, 541–553,Short summary
We investigate the stratospheric influence on marine cold air outbreaks (MCAOs) in the North Atlantic using ERA-Interim reanalysis data. MCAOs are associated with severe Arctic weather, such as polar lows and strong surface winds. Sudden stratospheric events are found to be associated with more frequent MCAOs in the Barents and the Norwegian seas, affected by the anomalous circulation over Greenland and Scandinavia. Identification of MCAO precursors is crucial for improved long-range prediction.
Rita Glowienka-Hense, Andreas Hense, Sebastian Brune, and Johanna Baehr
Adv. Stat. Clim. Meteorol. Oceanogr., 6, 103–113,Short summary
A new method for weather and climate forecast model evaluation with respect to observations is proposed. Individually added values are estimated for each model, together with shared information both models provide equally on the observations. Finally, shared model information, which is not present in the observations, is calculated. The method is applied to two examples from climate and weather forecasting, showing new perspectives for model evaluation.
Julianna C. Oliveira, Leonard Borchert, Aurélie Duchez, Mikhail Dobrynin, and Johanna Baehr
Weather Clim. Dynam. Discuss.,
Preprint under review for WCD
Nonlin. Processes Geophys., 27, 121–131,Short summary
Seasonal prediction of the of the North Atlantic Oscillation (NAO) has been improved in recent years by improving dynamical models and ensemble predictions. One step therein was the so-called sub-sampling, which combines statistical and dynamical predictions. This study generalises this approach and makes it much more accessible. Furthermore, it presents a new verification approach for such predictions.
Matthias Fischer, Daniela I. V. Domeisen, Wolfgang A. Müller, and Johanna Baehr
Earth Syst. Dynam., 8, 129–146,Short summary
In a climate projection experiment with the Max Planck Institute Earth System Model (MPI-ESM), we find that a decline in the Atlantic Ocean meridional heat transport (OHT) is accompanied by a change in the seasonal cycle of the total OHT and its components. We found a northward shift of 5° and latitude-dependent shifts between 1 and 6 months in the seasonal cycle that are mainly associated with changes in the meridional velocity field rather than the temperature field.
André Düsterhus, Alessio Rovere, Anders E. Carlson, Benjamin P. Horton, Volker Klemann, Lev Tarasov, Natasha L. M. Barlow, Tom Bradwell, Jorie Clark, Andrea Dutton, W. Roland Gehrels, Fiona D. Hibbert, Marc P. Hijma, Nicole Khan, Robert E. Kopp, Dorit Sivan, and Torbjörn E. Törnqvist
Clim. Past, 12, 911–921,Short summary
This review/position paper addresses problems in creating new interdisciplinary databases for palaeo-climatological sea-level and ice-sheet data and gives an overview on new advances to tackle them. The focus therein is to define and explain strategies and highlight their importance to allow further progress in these fields. It also offers important insights into the general problem of designing competitive databases which are also applicable to other communities within the palaeo-environment.
J. Baehr and R. Piontek
Geosci. Model Dev., 7, 453–461,
Related subject area
Subject: Hydrometeorology | Techniques and Approaches: Theory developmentThe precipitation variability of the wet and dry season at the interannual and interdecadal scales over eastern China (1901–2016): the impacts of the Pacific OceanFlash drought onset over the contiguous United States: sensitivity of inventories and trends to quantitative definitionsA skewed perspective of the Indian rainfall–El Niño–Southern Oscillation (ENSO) relationshipImprints of evaporative conditions and vegetation type in diurnal temperature variationsA review of the complementary principle of evaporation: from the original linear relationship to generalized nonlinear functionsModel representation of the coupling between evapotranspiration and soil water content at different depthsCombined impacts of ENSO and MJO on the 2015 growing season drought on the Canadian PrairiesExploring the relationships between warm-season precipitation, potential evaporation, and “apparent” potential evaporation at site scaleFuture extreme precipitation intensities based on a historic eventInterannual-to-multidecadal hydroclimate variability and its sectoral impacts in northeastern ArgentinaImpact of ENSO regimes on developing- and decaying-phase precipitation during rainy season in ChinaVariations in the correlation between teleconnections and Taiwan's streamflowA gain–loss framework based on ensemble flow forecasts to switch the urban drainage–wastewater system management towards energy optimization during dry periodsThe residence time of water in the atmosphere revisitedA systematic assessment of drought termination in the United KingdomFrom meteorological to hydrological drought using standardised indicatorsImpact of two different types of El Niño events on runoff over the conterminous United StatesFlood sensitivity of the Bavarian Alpine Foreland since the late Middle Ages in the context of internal and external climate forcing factorsNovel indices for the comparison of precipitation extremes and floods: an example from the Czech territoryMulti-annual droughts in the English Lowlands: a review of their characteristics and climate drivers in the winter half-yearFractional snow-covered area parameterization over complex topographyComment on "Technical Note: On the Matt–Shuttleworth approach to estimate crop water requirements" by Lhomme et al. (2014)A review of droughts on the African continent: a geospatial and long-term perspectiveSynchronicity of historical dry spells in the Southern HemisphereContinental moisture recycling as a Poisson processLinking ENSO and heavy rainfall events over coastal British Columbia through a weather pattern classificationImpact of elevation and weather patterns on the isotopic composition of precipitation in a tropical montane rainforestA new perspective on the spatio-temporal variability of soil moisture: temporal dynamics versus time-invariant contributionsUnderstanding hydroclimate processes in the Murray-Darling Basin for natural resources managementAn analytical model for soil-atmosphere feedbackSpatial horizontal correlation characteristics in the land data assimilation of soil moistureOn the factors influencing surface-layer energy closure and their seasonal variability over the semi-arid Loess Plateau of Northwest ChinaSpatial moments of catchment rainfall: rainfall spatial organisation, basin morphology, and flood responseScaling and trends of hourly precipitation extremes in two different climate zones – Hong Kong and the NetherlandsThe response of Iberian rivers to the North Atlantic OscillationCopula-based downscaling of spatial rainfall: a proof of conceptTowards understanding hydroclimatic change in Victoria, Australia – preliminary insights into the "Big Dry"Extracting statistical parameters of extreme precipitation from a NWP model
Tao Gao, Fuqiang Cao, Li Dan, Ming Li, Xiang Gong, and Junjie Zhan
Hydrol. Earth Syst. Sci., 25, 1467–1481,Short summary
The rainfall in eastern China is principally concentrated from April–September. Changes are roughly coincident with phase shifts of the El Niño–Southern Oscillation (ENSO) in both the dry (October–March) and wet (April–September) seasons, and the Pacific Decadal Oscillation (PDO) triggers a stronger effect on precipitation in the wet season. The interannual and interdecadal rainfall variability over eastern China is substantially modulated by drivers originating from the Pacific Ocean.
Mahmoud Osman, Benjamin F. Zaitchik, Hamada S. Badr, Jordan I. Christian, Tsegaye Tadesse, Jason A. Otkin, and Martha C. Anderson
Hydrol. Earth Syst. Sci., 25, 565–581,Short summary
Our study of flash droughts' definitions over the United States shows that published definitions yield markedly different inventories of flash drought geography and frequency. Results suggest there are several pathways that can lead to events that are characterized as flash droughts. Lack of consensus across definitions helps to explain apparent contradictions in the literature on trends and indicates the selection of a definition is important for accurate monitoring of different mechanisms.
Justin Schulte, Frederick Policielli, and Benjamin Zaitchik
Hydrol. Earth Syst. Sci., 24, 5473–5489,Short summary
Wavelet coherence is now a commonly used method for detecting scale-dependent relationships between time series. In this study, the concept of wavelet coherence is generalized to higher-order wavelet coherence methods that quantify the relationship between higher-order statistical moments associated with two time series. The methods are applied to the El Niño–Southern Oscillation (ENSO) and the Indian monsoon to show that the ENSO–Indian monsoon relationship is impacted by ENSO nonlinearity.
Annu Panwar, Maik Renner, and Axel Kleidon
Hydrol. Earth Syst. Sci., 24, 4923–4942,Short summary
Here we examine the effect of evaporative cooling across different vegetation types. Evaporation cools surface temperature significantly in short vegetation. In the forest, the high aerodynamic conductance explains 56 % of the reduced surface temperature. Therefore, the main cooling agent in the forest is the high aerodynamic conductance and not evaporation. Additionally, we propose the diurnal variation in surface temperature as being a potential indicator of evaporation in short vegetation.
Songjun Han and Fuqiang Tian
Hydrol. Earth Syst. Sci., 24, 2269–2285,Short summary
The complementary principle is an important methodology for estimating actual evaporation by using routinely observed meteorological variables. This review summaries its 56-year development, focusing on how related studies have shifted from adopting a symmetric linear complementary relationship to employing generalized nonlinear functions. We also compare the polynomial and sigmoid types of generalized complementary functions and discuss their future development.
Jianxiu Qiu, Wade T. Crow, Jianzhi Dong, and Grey S. Nearing
Hydrol. Earth Syst. Sci., 24, 581–594,Short summary
Accurately estimating coupling of evapotranspiration (ET) and soil water content (θ) at different depths is key to investigating land–atmosphere interaction. Here we examine whether the model can accurately represent surface θ (θs) versus ET coupling and vertically integrated θ (θv) versus ET coupling. We find that all models agree with observations that θs contains slightly more information with fPET than θv. In addition, an ET scheme is crucial for accurately estimating coupling of θ and ET.
Zhenhua Li, Yanping Li, Barrie Bonsal, Alan H. Manson, and Lucia Scaff
Hydrol. Earth Syst. Sci., 22, 5057–5067,Short summary
The research started by investigating the 2015 growing season drought over the Canadian Prairies and evolved into investigating the connection between growing season rain deficit in the Prairies and MJO (20–90 days tropical oscillation in convective storms). With warm central Pacific sea surface temperature, strong MJOs in the western Pacific cause Rossby wave trains that propagate downstream and favour upper-level ridges and rain deficits over the Canadian Prairies during the growing season.
Xi Chen and Steven G. Buchberger
Hydrol. Earth Syst. Sci., 22, 4535–4545,Short summary
Based on warm season data from 259 weather stations across the US, we analyze the correlation between precipitation, potential evaporation, and “apparent” potential evaporation (measured by pan evaporation). Over 93 % of the stations show negative correlation between precipitation and
apparentpotential evaporation, but no clear relationship is shown between precipitation and potential evaporation. The collected data points follow the trend of the newly derived Bouchet–Budyko curve.
Iris Manola, Bart van den Hurk, Hans De Moel, and Jeroen C. J. H. Aerts
Hydrol. Earth Syst. Sci., 22, 3777–3788,Short summary
In a warmer climate, it is expected that precipitation intensities will increase and form a considerable risk of high-impact precipitation extremes. We investigate how observed extreme precipitation events would look like if they took place in a future warmer climate. This study applies three methods to transform a historic extreme precipitation event in the Netherlands to a similar event in a future warmer climate, thus compiling a
Miguel A. Lovino, Omar V. Müller, Gabriela V. Müller, Leandro C. Sgroi, and Walter E. Baethgen
Hydrol. Earth Syst. Sci., 22, 3155–3174,Short summary
This study examines hydroclimate variability in northeastern Argentina; advances the understanding of its links with global SST forcing; and discusses its impacts on water resources, agriculture and human settlements. Interannual-to-multidecadal variability led to frequent extreme events. Severe floods affected agriculture, livestock productivity, and forced population displacements. Droughts affected water resources, causing water and food scarcity. Increased temperatures reduced crop yields.
Qing Cao, Zhenchun Hao, Feifei Yuan, Zhenkuan Su, Ronny Berndtsson, Jie Hao, and Tsring Nyima
Hydrol. Earth Syst. Sci., 21, 5415–5426,Short summary
This study analyzed the rainy-season precipitation in China influenced by various ENSO types. The precipitation anomalies were investigated under different ENSO types, which may be attributed to the combined influence of anti-cyclone in the western North Pacific and the Indian monsoon. The results improve the understanding of linkages between the precipitation and global teleconnection patterns. The results suggest a certain predictability of flood and drought related to different ENSO types.
Chia-Jeng Chen and Tsung-Yu Lee
Hydrol. Earth Syst. Sci., 21, 3463–3481,Short summary
Regional hydro-climatic variables are modulated by large-scale, reoccurring climate oscillations. In this article, the authors provide both statistical and physical evidence of how Taiwan’s summertime streamflow is strongly correlated with specific teleconnection patterns dominating cyclonic activity in the western North Pacific. However, such correlation can be strengthened or weakened by notable climate regime shifts, illustrating the pitfall of empirical seasonal forecasting.
Vianney Courdent, Morten Grum, Thomas Munk-Nielsen, and Peter S. Mikkelsen
Hydrol. Earth Syst. Sci., 21, 2531–2544,Short summary
Urban drainage and wastewater systems are heavily impacted by precipitation. Hence, weather forecasts are valuable in improving their management. However, forecasts are intrinsically uncertain, especially when fine model resolution is required, which is the case for urban hydrology. Handling uncertainty is challenging for decision makers. This study presents an economic framework to support the decision-making process by providing information on when acting on the forecast is beneficial.
Ruud J. van der Ent and Obbe A. Tuinenburg
Hydrol. Earth Syst. Sci., 21, 779–790,Short summary
This research seeks out to answer a fundamental question about the functioning of the water cycle in the atmosphere: how much time does a water particle spend in the atmosphere? Based on state-of-the-art data, we derive a global average residence time of water in the atmosphere of 8–10 days. We further show in this paper how the residence time of water varies in time and space. This serves to illustrate why it is so difficult to make weather predictions on timescales longer than a week.
Simon Parry, Robert L. Wilby, Christel Prudhomme, and Paul J. Wood
Hydrol. Earth Syst. Sci., 20, 4265–4281,Short summary
This paper identifies periods of recovery from drought in 52 river flow records from the UK between 1883 and 2013. The approach detects 459 events that vary in space and time. This large dataset allows individual events to be compared with others in the historical record. The ability to objectively appraise contemporary events against the historical record has not previously been possible, and may allow water managers to prepare for a range of outcomes at the end of a drought.
Lucy J. Barker, Jamie Hannaford, Andrew Chiverton, and Cecilia Svensson
Hydrol. Earth Syst. Sci., 20, 2483–2505,Short summary
Standardised meteorological indicators are widely used in drought monitoring, but applications to hydrological drought are less extensive. Here we assess the utility of standardised indicators for characterising drought duration, severity and propagation in a diverse set of 121 UK catchments. Spatial variations in streamflow drought characteristics reflect differences in drought propagation behaviour that are themselves largely driven by heterogeneity in catchment properties around the UK.
T. Tang, W. Li, and G. Sun
Hydrol. Earth Syst. Sci., 20, 27–37,
O. Böhm, J. Jacobeit, R. Glaser, and K.-F. Wetzel
Hydrol. Earth Syst. Sci., 19, 4721–4734,
M. Müller, M. Kašpar, A. Valeriánová, L. Crhová, E. Holtanová, and B. Gvoždíková
Hydrol. Earth Syst. Sci., 19, 4641–4652,Short summary
Three proposed indices combine return periods of precipitation totals or discharges with the size of the affected area. Precipitation indices also determine actual duration of either extreme or seasonally abnormal precipitation events. A unified design of the indices enables one to easily compare inter-annual and seasonal distributions of events, which is demonstrated by 50 maximum events in the Czech Republic during the period 1961-2010, including the June 2013 floods.
C. K. Folland, J. Hannaford, J. P. Bloomfield, M. Kendon, C. Svensson, B. P. Marchant, J. Prior, and E. Wallace
Hydrol. Earth Syst. Sci., 19, 2353–2375,Short summary
The English Lowlands is a heavily populated, water-stressed region, which is vulnerable to long droughts typically associated with dry winters. We conduct a long-term (1910-present) quantitative analysis of precipitation, flow and groundwater droughts for the region, and then review potential climatic drivers. No single driver is dominant, but we demonstrate a physical link between La Nina conditions, winter rainfall and long droughts in the region.
N. Helbig, A. van Herwijnen, J. Magnusson, and T. Jonas
Hydrol. Earth Syst. Sci., 19, 1339–1351,
W. J. Shuttleworth
Hydrol. Earth Syst. Sci., 18, 4403–4406,Short summary
This paper explains the Matt-Shuttleworth approach clearly, simply and concisely. It shows how this approach can be implemented using a few simple equations and provides access to ancillary calculation resources that can be used for such implementation. If the crop water requirement community considered it preferable to use the Penman-Monteith equation to estimate crop water requirements directly for all crops, this could now be done using the Matt-Shuttleworth approach.
I. Masih, S. Maskey, F. E. F. Mussá, and P. Trambauer
Hydrol. Earth Syst. Sci., 18, 3635–3649,
D. C. Verdon-Kidd and A. S. Kiem
Hydrol. Earth Syst. Sci., 18, 2257–2264,
H. F. Goessling and C. H. Reick
Hydrol. Earth Syst. Sci., 17, 4133–4142,
P. Brigode, Z. Mićović, P. Bernardara, E. Paquet, F. Garavaglia, J. Gailhard, and P. Ribstein
Hydrol. Earth Syst. Sci., 17, 1455–1473,
D. Windhorst, T. Waltz, E. Timbe, H.-G. Frede, and L. Breuer
Hydrol. Earth Syst. Sci., 17, 409–419,
H. Mittelbach and S. I. Seneviratne
Hydrol. Earth Syst. Sci., 16, 2169–2179,
A. J. E. Gallant, A. S. Kiem, D. C. Verdon-Kidd, R. C. Stone, and D. J. Karoly
Hydrol. Earth Syst. Sci., 16, 2049–2068,
B. Schaefli, R. J. van der Ent, R. Woods, and H. H. G. Savenije
Hydrol. Earth Syst. Sci., 16, 1863–1878,
X. Han, X. Li, H. J. Hendricks Franssen, H. Vereecken, and C. Montzka
Hydrol. Earth Syst. Sci., 16, 1349–1363,
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Hydrol. Earth Syst. Sci., 16, 893–910,
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Hydrol. Earth Syst. Sci., 15, 3767–3783,
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Hydrol. Earth Syst. Sci., 15, 3033–3041,
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The Standardized Precipitation Index (SPI) is a widely accepted drought index. SPI normalizes the precipitation distribution via a probability density function (PDF). However, which PDF properly normalizes SPI is still disputed. We suggest using a previously mostly overlooked PDF, namely the exponentiated Weibull distribution. The proposed PDF ensures the normality of the index. We demonstrate this – for the first time – for all common accumulation periods in both observations and simulations.
The Standardized Precipitation Index (SPI) is a widely accepted drought index. SPI normalizes...