Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Hydro-Climatic Variability and Change in Central America: Supporting Risk Reduction Through Improved Analyses and Data
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Centre for Geophysical Resarch, University of Costa Rica. (LUVAL)ORCID iD: 0000-0001-9861-3451
2017 (English)Doctoral thesis, comprehensive summary (Other academic)Alternative title
Variabilitet och förändring av hydrologi och klimat i Mellanamerika : Stöd för riskreducering genom förbättrade analyser och data (Swedish)
Description
Abstract [en]

Floods and droughts are frequent in Central America and cause large social, economic and environmental impacts. A crucial step in disaster risk reduction is to have a good understanding of the causing mechanisms of extreme events and their spatio-temporal characteristics. For this, a key aspect is access to a dense network of long and good-quality hydro-meteorological data. Unfortunately, such ideal data are sparse or non-existent in Central America. In addition, the existing methods for hydro-climatic studies need to be revised and/or improved to find the most suitable for the region’s climate, geography and hydro-climatic data situation. This work has the ultimate goal to support the reduction of risks associated with hydro-climatic-induced disasters in Central America. This was sought by developing ways to reduce data-related uncertainties and by improving the available methods to study and understand hydro-climatic variability processes. In terms of data-uncertainty reduction, this thesis includes the development of a high resolution air temperature dataset and a methodology to reduce uncertainties in a hydrological model at ungauged basins. The dataset was able to capture the spatial patterns with a detail not available with existing datasets. The methodology significantly reduced uncertainties in an assumed-to-be ungauged catchment. In terms of methodological improvements, this thesis includes an assessment of the most suitable combination of (available) meteorological datasets and drought indices to characterise droughts in Central America. In addition, a methodology was developed to analyse drought propagation in a tropical catchment, in an automated, objective way. Results from the assessment and the drought propagation analysis contributed with improving the understanding of drought patterns and generating processes in the region. Finally, a methodology was proposed for assessing changes in both hydrological extremes in a consistent way. This contrasts with most commonly used frameworks that study each extreme individually. The method provides important characteristics (frequency, duration and magnitude), information that can be useful for decisions within risk reduction and water management. The results presented in this thesis are a contribution, in terms of hydro-climatic data and assessment methods, for supporting risk reduction of disasters related with hydro-climatic extremes in Central America.

Abstract [sv]

Översvämningar och torka inträffar ofta i Mellanamerika och orsakar stora skador på samhälle, ekonomi och miljö. En kritisk del av riskreduceringen är förståelsen av mekanismerna bakom extremhändelserna, och deras rumsliga och tidskarakteristik. En nyckelfaktor är tillgång till långa tidsserier av rumsligt täckande hydrometeorologiska data av bra kvalitet. I Mellanamerika är sådana ideala data tyvärr sällsynta eller saknas helt. Dessutom behöver befintliga metoder för hydro-klimatisk analys revideras och/eller förbättras för att identifiera de mest lämpade metoderna för regionens klimat, geografi och situationen vad gäller hydrologiska och meteorologiska data. Det övergripande syftet med denna avhandling har varit att stödja arbetet med riskreducering i Mellanamerika vid hydrologiska extremhändelser som sätts igång av extrema väderhändelser. För att bidra till detta utvecklades metoder för att minska datarelaterade osäkerheter och för att förbättra tillgängliga metoder för att studera och förstå de processer som ligger bakom variabiliteten i hydrologi och klimat. Dataosäkerheten minskades genom utveckling av ett nytt dataset för lufttemperatur med hög rumslig upplösning och en metodik för att begränsa osäkerheten i modellberäknad vattenföring i ett område där det saknas observationer. Det nya datasetet kunde fånga rumsliga mönster på en detaljnivå som hittills inte varit möjlig. Metodiken möjliggjorde en klar minskning i osäkerheten hos vattenföringen i ett avrinningsområde som behandlades som om det saknade data. Avhandlingen innehåller också en metodik för att fastlägga den mest lämpade kombinationen av tillgängliga klimatdataset och torkindex för att karakterisera torka i Mellanamerika. Därutöver utvecklades en metod för att studera torkans fortplantning i ett tropiskt avrinningsområde på ett objektivt och automatiserat sätt. Slutligen föreslås en metod för att hantera förändringar av både översvämning och torka på ett konsistent sätt  som förenklar användningen av resultaten  för en beslutsfattare. Dessa metoder bedömdes användbara för att förbättra karakteriseringen och förståelsen av extrema hydrologiska händelser i Mellanamerika. Resultaten i denna avhandling ger bidrag till förståelsen av hydrologiska och klimatextremer genom förbättrade data och analysmetoder som i förlängningen kommer att stödja riskreduceringsarbetet i Mellanamerika.

Abstract [es]

Las sequías e inundaciones son frecuentes en Centroamérica y causan grandes problemas sociales, económicos y ambientales. Un aspecto crucial en la reducción del riesgo consiste en entender los mecanismos que causan dichos eventos, y sus características espacio-temporales. Para lograr esto es necesario tener acceso a una red de datos hidro-meterológicos densa, con series largas, y de buena calidad. Desafortunadamente, este no es el caso en Centroamérica. Además, los métodos para hacer estudios hidro-climáticos requieren ser evaluados y/o mejorados para asegurar su aplicabilidad en la región (su clima, su geografía y los datos disponibles). Este trabajo tiene como meta apoyar la reducción del riesgo de desastres asociados a eventos hidro-meteorológicos extremos en Centroamérica. Esto se consigue a partir de la reducción de incertidumbres asociadas a los datos, y de la mejora de métodos para el estudio de la variabilidad hidro-climática. Para reducir la incertidumbre de los datos, este trabajo incluye el desarrollo de una base de datos de temperatura de alta resolución y el desarrollo de una metodología para reducir las incertidumbres en datos simulados de caudal. Con la nueva base de datos se logra reconocer patrones espaciales a un nivel de detalle no antes captado por otras bases de datos. Por otro lado, la metodología redujo significativamente las incertidumbres de los datos simulados de caudal. En cuanto a métodos, esta tesis incluye una evaluación para encontrar la mejor combinación de índices de sequía y base de datos para la caracterización de sequías en la región. Además, se desarrolló una metodología para analizar la propagación de la sequía en una cuenca tropical, de una manera objetiva y automatizada. Los resultados de estos dos pasos ayudaron a mejorar la comprensión de los patrones y los mecanismos de generación de las sequías. Finalmente, se incluyó un método para evaluar los cambios en los patrones de sequías e inundaciones de una manera consistente, y no de manera individual como usualmente se ha hecho. Así fue posible obtener la frecuencia, duración y magnitud en ambos extremos hidrológicos. Esta información podría constituir una herramienta  útil para el manejo del riesgo y del recurso hídrico.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2017. , 70 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1570
Keyword [en]
Central America, climate variability, disaster risk reduction, droughts, drought indices, floods, hydrological model, process constraints, statistical downscaling, uncertainty, ungauged basins, water resources.
National Category
Oceanography, Hydrology, Water Resources
Research subject
Hydrology
Identifiers
URN: urn:nbn:se:uu:diva-330814ISBN: 978-91-513-0092-4 (print)OAI: oai:DiVA.org:uu-330814DiVA: diva2:1147436
Public defence
2017-11-24, Axel Hambergsalen, Earth Sciences Centre, Villavägen 16, Uppsala, 10:00 (English)
Opponent
Supervisors
Available from: 2017-10-31 Created: 2017-10-05 Last updated: 2017-10-31
List of papers
1. Observed (1970-1999) climate variability in Central America using a high-resolution meteorological dataset with implication to climate change studies
Open this publication in new window or tab >>Observed (1970-1999) climate variability in Central America using a high-resolution meteorological dataset with implication to climate change studies
2017 (English)In: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 141, no 1, 13-28 p.Article in journal (Refereed) Published
Abstract [en]

High spatial resolution of precipitation (P) and average air temperature (Tavg) datasets are ideal for determining the spatial patterns associated with large-scale atmospheric and oceanic indexes, and climate change and variability studies, however such datasets are not usually available. Those datasets are particularly important for Central America because they allow the conception of climate variability and climate change studies in a region of high climatic heterogeneity and at the same time aid the decisionmaking process at the local scale (municipalities and districts). Tavg data from stations and complementary gridded datasets at 50 km resolution were used to generate a high-resolution (5 km grid) dataset for Central America from 1970 to 1999. A highresolution P dataset was used along with the new Tavg dataset to study climate variability and a climate change application. Consistently with other studies, it was found that the 1970-1999 trends in P are generally non-significant, with the exception of a few small locations. In the case of Tavg, there were significant warming trends in most of Central America, and cooling trends in Honduras and northern Panama. When the sea surface temperature anomalies between the Tropical Pacific and the Tropical Atlantic have different (same) sign, they are a good indicator of the sign of P (Tavg) annual anomalies. Even with non-significant trends in precipitation, the significant warming trends in Tavg in most of Central America can have severe consequences in the hydrology and water availability of the region, as the warming would bring increases in evapotranspiration, drier soils and higher aridity.

Place, publisher, year, edition, pages
Springer, 2017
National Category
Climate Research
Identifiers
urn:nbn:se:uu:diva-320295 (URN)10.1007/s10584-016-1786-y (DOI)000395201500002 ()
Available from: 2017-04-25 Created: 2017-04-25 Last updated: 2017-10-05Bibliographically approved
2. Can climate variability information constrain a hydrologicalmodel for an ungauged Costa Rican catchment?
Open this publication in new window or tab >>Can climate variability information constrain a hydrologicalmodel for an ungauged Costa Rican catchment?
Show others...
(English)In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085Article in journal (Other academic) Submitted
Place, publisher, year, edition, pages
John Wiley & Sons
Keyword
Uncertainty, ungauged basins, climate variability, hydrological model, Central America, process constraints
National Category
Oceanography, Hydrology, Water Resources
Identifiers
urn:nbn:se:uu:diva-317262 (URN)
Available from: 2017-03-12 Created: 2017-03-12 Last updated: 2017-10-05
3. Characterising droughts in Central America with uncertain hydro-meteorological data
Open this publication in new window or tab >>Characterising droughts in Central America with uncertain hydro-meteorological data
Show others...
(English)In: Journal of Theoretical and Applied Climatology, ISSN 0177-798X, E-ISSN 1434-4483Article in journal (Refereed) Submitted
Keyword
droughts; scarce data; Central America; drought indices
National Category
Oceanography, Hydrology, Water Resources
Research subject
Hydrology; Meteorology
Identifiers
urn:nbn:se:uu:diva-330134 (URN)
Funder
Sida - Swedish International Development Cooperation Agency, 54100006
Available from: 2017-09-26 Created: 2017-09-26 Last updated: 2017-10-05
4. Automation of hydrological drought typology to study drought propagation in a tropical catchment
Open this publication in new window or tab >>Automation of hydrological drought typology to study drought propagation in a tropical catchment
Show others...
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Understanding different types of drought and how they propagate through the hydrological cycle from precipitation to streamflow and groundwater deficits is important for improving water and risk management policies. Drought in the tropics is a recurrent phenomenon, but limited knowledge exists about drought severity and duration as well as the processes that cause different types of drought. At the catchment scale, analysing drought propagation is usually done manually. This can be time consuming (e.g. when dealing with long time series or many catchments) and may introduce subjective elements into the analysis that affect the comparability between catchments and studies. In this study, we developed a methodology to provide an automated objective procedure for drought typology to study hydrological drought propagation in the tropics.  We selected the Savegre catchment in Costa Rica as a proof-of-concept pilot study. The first step was to analyse if the types of drought affecting this catchment could be explained in terms of the process-based typology available in the literature: classical rainfall deficit drought, wet-to-dry season drought, and composite drought. Then, based on the manual typology, we defined different criteria for the hydrological drought types to make the typology automated and objective. Finally, we analysed drought propagation using a set of duration, timing and deficit indicators. We found that the process-based hydrological typology available in the literature is suitable to describe the different drought processes occurring in Savegre. The classification obtained with the automated typology was highly similar to the manual typology, with the exception of one event. We found that most of the detected droughts (71% and 73% from all river discharge and groundwater droughts, respectively) were classical rainfall deficits droughts, which suggests that droughts in this catchment are highly climate dominated. However, the importance of storage control was reflected during the dry season, when some of the longest and most severe events took place. The most severe events were composite and wet-to-dry season droughts, but we also found highly severe classical rainfall deficits droughts. Our results can potentially be applied to the wider tropics facilitating automatic drought classification using process-based selection criteria. Our study contributes to the overall knowledge of drought propagation in tropical catchments and is useful for supporting drought monitoring and forecasting, which is a much needed tool for water and drought-related disaster management in the tropics. 

Keyword
drought propagation; drought typology; automation; tropical catchment; Central America; Costa Rica
National Category
Oceanography, Hydrology, Water Resources
Research subject
Hydrology
Identifiers
urn:nbn:se:uu:diva-330122 (URN)
Available from: 2017-10-05 Created: 2017-10-05 Last updated: 2017-10-05
5. Hydrological change: towards a consistent approach to assess changes on both floods and droughts
Open this publication in new window or tab >>Hydrological change: towards a consistent approach to assess changes on both floods and droughts
(English)In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657Article in journal (Refereed) Submitted
Place, publisher, year, edition, pages
Elsevier
Keyword
hydrological changes; threshold level method; floods; droughts
National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:uu:diva-330119 (URN)
Funder
Sida - Swedish International Development Cooperation Agency, 54100006
Available from: 2017-09-26 Created: 2017-09-26 Last updated: 2017-10-05

Open Access in DiVA

fulltext(1326 kB)28 downloads
File information
File name FULLTEXT01.pdfFile size 1326 kBChecksum SHA-512
36bb8dfc109ed4095e383e5d406d33400a9a187d506ecac30798e27ce1ac750333a4b4934479f4a7c2c4a308588acc68d4b8a36438487ee1c3a175914eee4e79
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Quesada-Montano, Beatriz
By organisation
Department of Earth Sciences
Oceanography, Hydrology, Water Resources

Search outside of DiVA

GoogleGoogle Scholar
Total: 28 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 242 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf