Statistical modelling of extreme rainfall in Madeira Island

Extreme rainfall events have triggered a significant number of flash floods in Madeira Island along its past and recent history. Madeira is a volcanic island where the spatial rainfall distribution is strongly affected by its rugged topography. In this thesis, annual maximum of daily rainfall data from 25 rain gauge stations located in Madeira Island were modelled by the generalised extreme value distribution. Also, the hypothesis of a Gumbel distribution was tested by two methods and the existence of a linear trend in both distributions parameters was analysed. Estimates for the 50– and 100–year return levels were also obtained. Still in an univariate context, the assumption that a distribution function belongs to the domain of attraction of an extreme value distribution for monthly maximum rainfall data was tested for the rainy season. The available data was then analysed in order to find the most suitable domain of attraction for the sampled distribution. In a different approach, a search for thresholds was also performed for daily rainfall values through a graphical analysis. In a multivariate context, a study was made on the dependence between extreme rainfall values from the considered stations based on Kendall’s τ measure. This study suggests the influence of factors such as altitude, slope orientation, distance between stations and their proximity of the sea on the spatial distribution of extreme rainfall. Groups of three pairwise associated stations were also obtained and an adjustment was made to a family of extreme value copulas involving the Marshall–Olkin family, whose parameters can be written as a function of Kendall’s τ association measures of the obtained pairs.

Tendências hidrológicas anuais e sazonais na bacia do Rio Paraibuna, Parque Estadual da Serra do Mar (SP)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hochwasser-«Katastrophen» in Basel vom 13. bis 21. Jahrhundert Rekonstruktion, Deutung und Lerneffekte

Magnitudes of peak discharges of 43 non-instrumentally measured Rhine river floods at Basel were reconstructed. The methodology is based on a range of different historic sources, containing flood information (including traditional urban inundation reference points from flood reports of medieval and early modern period chroniclers as well as 19th century journalists, flood marks, paintings and drawings, town maps, longitudinal and cross profiles etc.). These traditional pre-instrumental “flood information systems” still existed in the 19th century, when in 1808 the first instrumental hydrological measurements started. They thus could be calibrated with instrumental measurements in the 19th century overlapping period. The result is a 743 year long quantified Rhine river flood series. Floods of both periods (pre-instrumental as well as instrumental) can thus be directly compared for the very first time. The long-range consequences of rivers Kander and Aare deviations in 1714 and 1878 are reflected in a distinct change of magnitudes of peak discharges in Basel. A clear flood “disaster gap” appears in the 20th century. The lack of any extreme floods for such a long time is completely unique during the 743-year period of analysis. This result will influence the statistical assessment of once-in-a-century events, which might be of great interest for insurance campanies.

New insights into the reconstructed temperature in Portugal over the last 400 years

The consistency of an existing reconstructed annual (December–November) temperature series for the Lisbon region (Portugal) from 1600 onwards, based on a European-wide reconstruction, with (1) five local borehole temperature–depth profiles; (2) synthetic temperature– depth profiles, generated from both reconstructed temperatures and two regional paleoclimate simulations in Portugal; (3) instrumental data sources over the twentieth century; and (4) temperature indices from documentary sources during the late Maunder Minimum (1675–1715) is assessed. The low-frequency variability in the reconstructed temperature in Portugal is not entirely consistent with local borehole temperature–depth profiles and with the simulated response of temperature in two regional paleoclimate simulations driven by reconstructions of various climate forcings. Therefore, the existing reconstructed series is calibrated by adjusting its low-frequency variability to the simulations (first-stage adjustment). The annual reconstructed series is then calibrated in its location and scale parameters, using the instrumental series and a linear regression between them (second-stage adjustment). This calibrated series shows clear footprints of the Maunder and Dalton minima, commonly related to changes in solar activity and explosive volcanic eruptions, and a strong recent-past warming, commonly related to human-driven forcing. Lastly, it is also in overall agreement with annual temperature indices over the late Maunder Minimum in Portugal. The series resulting from this post-reconstruction adjustment can be of foremost relevance to improve the current understanding of the driving mechanisms of climate variability in Portugal.

Field measurements of the atmosphere, ocean, sea ice and sub-ice platelet layer at Atka Bay in 2013

Ice shelves strongly interact with coastal Antarctic sea ice and the associated ecosystem by creating conditions favourable to the formation of a sub-ice platelet layer. The close investigation of this phenomenon and its seasonal evolution remain a challenge due to logistical constraints and a lack of suitable methodology. In this study, we characterize the seasonal cycle of Antarctic fast ice adjacent to the Ekström Ice Shelf in the eastern Weddell Sea. We used a thermistor chain with the additional ability to record the temperature response induced by cyclic heating of resistors embedded in the chain. Vertical sea-ice temperature and heating profiles obtained daily between November 2012 and February 2014 were analyzed to determine sea-ice and snow evolution, and to calculate the basal energy budget. The residual heat flux translated into an ice-volume fraction in the platelet layer of 0.18 ± 0.09, which we reproduced by a independent model simulation and agrees with earlier results. Manual drillings revealed an average annual platelet-layer thickness increase of at least 4m, and an annual maximum thickness of 10m beneath second-year sea ice. The oceanic contribution dominated the total sea-ice production during the study, effectively accounting for up to 70% of second-year sea-ice growth. In summer, an oceanic heat flux of 21 W/m**2 led to a partial thinning of the platelet layer. Our results further show that the active heating method, in contrast to the acoustic sounding approach, is well suited to derive the fast-ice mass balance in regions influenced by ocean/ice-shelf interaction, as it allows sub-diurnal monitoring of the platelet-layer thickness.

Using ground-penetrating radar, topography and classification of vegetation to model the sediment and active layer thickness in a periglacial lake catchment, Western Greenland, link to shapefiles

The geometries of a catchment constitute the basis for distributed physically based numerical modeling of different geoscientific disciplines. In this paper results from ground-penetrating radar (GPR) measurements, in terms of a 3D model of total sediment thickness and active layer thickness in a periglacial catchment in western Greenland, is presented. Using the topography, thickness and distribution of sediments is calculated. Vegetation classification and GPR measurements are used to scale active layer thickness from local measurements to catchment scale models. Annual maximum active layer thickness varies from 0.3 m in wetlands to 2.0 m in barren areas and areas of exposed bedrock. Maximum sediment thickness is estimated to be 12.3 m in the major valleys of the catchment. A method to correlate surface vegetation with active layer thickness is also presented. By using relatively simple methods, such as probing and vegetation classification, it is possible to upscale local point measurements to catchment scale models, in areas where the upper subsurface is relatively homogenous. The resulting spatial model of active layer thickness can be used in combination with the sediment model as a geometrical input to further studies of subsurface mass-transport and hydrological flow paths in the periglacial catchment through numerical modelling.

Long term economic growth, 1860-1965.

Brings together almost 400 aggregate annual economic time series and almost 800 component series that seem useful for studying economic growth.

Report of progress - Geological Survey of Canada.

Contents of each report may be found in "List of publications of the Geological survey of Canada. 1906."

Hydrologic data for experimental agricultural watersheds in the United States /

Description based on: 1971.

Collection of measurements on environmental conditions in plots of the Jena Experiment (time series since 2002)

This collection contains measurements of environmental conditions measured on the plots of the different sub-experiments at the field site of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. The following series of datasets are contained in this collection: 1.Soil temperature measurements on plots of the Main Experiment; 2. Quantification of the duration that individual plots of the Main Experiment were submerged during a flooding event occurring in June 2013

Iowa Flood Mitigation Board Annual Report, 2013

The Iowa Flood Mitigation Program is created within Code of Iowa, Chapter 418. The Program seeks to provide funds for flood mitigation projects that otherwise would not be funded. The Flood Mitigation Board is responsible for the implementation Code of Iowa Chapter 418. The membership of the Board is comprised of four voting public members appointed by the Governor, five voting members representing state agencies, and four non-voting ex-officio members of the legislature.

Iowa Flood Mitigation Board Annual Report, 2014

The Iowa Flood Mitigation Program is created within Code of Iowa, Chapter 418. The Program seeks to provide funds for flood mitigation projects that otherwise would not be funded. The Flood Mitigation Board is responsible for the implementation Code of Iowa Chapter 418. The membership of the Board is comprised of four voting public members appointed by the Governor, five voting members representing state agencies, and four non-voting ex-officio members of the legislature.

Iowa Flood Mitigation Board Annual Report, 2015

The Iowa Flood Mitigation Program is created within Code of Iowa, Chapter 418. The Program seeks to provide funds for fl ood mitigation projects that otherwise would not be funded. The Flood Mitigation Board is responsible for the implementation of Code of Iowa Chapter 418. The membership of the Board is comprised of four voting public members appointed by the Governor, five voting members representing state agencies, four non-voting ex officio members of the legislature, and one non-voting ex officio member representing a state agency.