Estimating predictive hydrological uncertainty by dressing deterministic and ensemble forecasts; a comparison, with application to Meuse and Rhine

Two statistical post-processing approaches for estimation of predictive hydrological uncertainty are compared: (i) ‘dressing’ of a deterministic forecast by adding a single, combined estimate of both hydrological and meteorological uncertainty and (ii) ‘dressing’ of an ensemble streamflow forecast by adding an estimate of hydrological...

A comparison of two global datasets of extreme sea levels and resulting flood exposure

Estimating the current risk of coastal flooding requires adequate information on extreme sea levels. For over a decade, the only global data available was the DINAS-COAST Extreme Sea Levels (DCESL) dataset, which applies a static approximation to estimate extreme sea levels. Recently, a dynamically derived dataset was developed: the Global...

Challenges in microbial ecology: Building predictive understanding of community function and dynamics

The importance of microbial communities (MCs) cannot be overstated. MCs underpin the biogeochemical cycles of the earth's soil, oceans and the atmosphere, and perform ecosystem functions that impact plants, animals and humans. Yet our ability to predict and manage the function of these highly complex, dynamically changing communities is...

Field Observations of Surf Zone-Inner Shelf Exchange on a Rip-Channeled Beach

Cross-shore exchange between the surf zone and the inner shelf is investigated using Lagrangian and Eulerian field measurements of rip current flows on a rip-channeled beach in Sand City, California. Surface drifters released on the inner shelf during weak wind conditions moved seaward due to rip current pulses and then returned shoreward in an...

Transport of larvae and detritus across the surf zone of a steep reflective pocket beach

Larvae of many intertidal species develop offshore and must cross the surf zone to complete their onshore migration to adult habitats. Depending on hydrodynamics, the surf zone may limit this migration, especially on reflective rocky shores. As a logistically tractable analog of a rocky shore environment, we carried out a comprehensive...

Evanescent wave coupling in a geophysical system: Airborne acoustic signals from the Mw 8.1 Macquarie Ridge earthquake

Atmospheric low-frequency sound, i.e., infrasound, from underwater events has not been considered thus far, due to the high impedance contrast of the water-air interface making it almost fully reflective. Here we report for the first time on atmospheric infrasound from a large underwater earthquake (Mw 8.1) near the Macquarie Ridge, which was...

TU students sweep UAV design competition

To design a high-altitude long-endurance UAV to fly a twenty-hour reconnaissance mission at an altitude of 80,000ft, was the assignment for this year’s undergraduate design competition. The competition was organized by the American Institute of Aeronautics and Astronautics (AIAA). Three students from Delft demonstrated superior design skills,...

The Chelyabinsk airburst: Implications for the Impact Hazard

Observations and modeling of steep-beach grain-size variability

Novel observations of surface grain-size distributions are used in combination with intra-wave modeling to examine the processes responsible for the sorting of sediment grains on a relatively steep beach (slope?=?1:7.5). The field observations of the mean grain size collected with a digital camera system at consecutive low and high tides for a 2...

The role of policy in supporting the private rented sector: International comparisons

The size of the private rented housing sector (PRS) varies markedly between coun-tries. The paper explores the role of policy in supporting the PRS with emphasis on the evidence from France, Germany, the UK and the USA. The definition and meas-urement of the size of the sector in each country is considered. A key issue that is explored is the...

Using the private rented sector as a form of social housing

The paper considers the role of the private rented sector in supplying housing that can be defined as social housing. It will do this by considering policy initiatives in Germany, France, the USA and England that use privately owned housing to meet social needs. The operation of these initiatives will be compared. The allocation and rent...

Surf zone diffusivity on a rip-channeled beach

Absolute and relative diffusivity are measured on a rip-channeled beach using 30 position-tracking drifters released in clusters (4–12 drifters) deployed on 7 days with different wave forcing and tidal elevations at Sand City, Monterey Bay, California. Diffusivity and dispersion were found to be larger on days with rip current flow patterns and...

Surf zone surface retention on a rip?channeled beach

The retention of floating matter within the surf zone on a rip-channeled beach is examined with a combination of detailed field observations obtained during the Rip Current Experiment and a three-dimensional (3-D) wave and flow model. The acoustic Doppler current profiler–observed hourly vertical cross-shore velocity structure variability over a...

Predicting the Future from Past Experience

What determines asset management approaches in the social rented sector?