: Global change, including climate change, poses unique challenges to the Department of Defense (DoD). In particular, coastal military sites, and their associated natural and built infrastructure, operations, and readiness capabilities, are vulnerable to the impacts of rising global sea level and local extreme water level (EWL) events. One way to assess vulnerabilities and impacts is to pose plausible and scientifically credible future conditions, or scenarios, with regard to sea level and EWLs. A multi-agency group conducted a literature synthesis and applied research effort to develop such scenarios. This report and its accompanying scenario database provide regionalized sea level and EWL scenarios for three future time horizons (2035, 2065, and 2100) for 1,774 DoD sites worldwide. The global nature of DoDs presence required a broad and comprehensive approach that to this point has been lacking in similar efforts. These regionalized scenarios were based on five global sea-level rise (SLR) scenarios. The site specific results reflect the fact that SLR is not uniform across the globe. The set of five global SLR scenarios (starting from 1992 and ranging from 0.2 meters to 2.0 meters by 2100) was developed consistent with other efforts of a similar nature that attempt to frame the plausible range of risk of concern to coastal managers. The suite of global scenarios and their associated storylines enable decision-makers to tailor their use of the scenarios to the decision under consideration and other factors. Although the scenarios extend only to the year 2100, for all global scenarios considered, sea levels will continue to rise past 2100. Decision-makers and planners with time horizons that go beyond 2100 should take this into account.

We use the standard deviation (sigma) of continuous 1 s water level sampling at 46 U.S. NOAA tide gauges available since 1996 as a high-frequency variance measure. Sigma estimates local infragravity and incident wave band variability, is significantly correlated (r = 0.5-0.9) to significant wave height (H-s), and scales linearly to local observations and output from the global ocean wave reanalysis at most ocean-exposed and harbor-sheltered locations. Empirical orthogonal functions of daily mean sigma from six Hawaii tide gauges distinguish northerly and southerly modes that closely match local Hs observations. Depending on tide gauge location, the 99% of daily maxima sigma can be as large as or larger than the nontidal residual component of the water level sample. Our findings provide new uses of land-based tide gauge data to estimate significant wave heights and dynamic water levels to better monitor for local conditions leading to impacts.

A method is presented to consistently tie future mean sea level rise (MSLR) scenario projections to local geodetic and tidal datums. This extends the U. S. Army Corps of Engineer (USACE) guidance for incorporating the effects of future MSLR into coastal projects. While USACE relies on the National Oceanic and Atmospheric Administration (NOAA) 19-year National Tidal Datum Epoch (NTDE) for its datum relationships, the approach proposed herein generalizes this guidance by choosing the appropriate 19-year epoch centered on the start year of the MSLR scenario under consideration. The procedure takes into account the local annual sea level variability, which confounds the matching to any given single year while generalizing and preserving the 19-year averaging long used by NOAA to calculate the NTDE. Examples of the MSLR scenario matching procedure are given using actual data and projections for La Jolla, California, and Sewells Point (Hampton Roads), Virginia. DOI: 10.1061/(ASCE)WW.1943-5460.0000145. (C) 2013 American Society of Civil Engineers.

The use of the term “integration” in the oceanographic world is now ingrained in governmental infrastructure for strategic planning and program implementation. Indeed, the National Office for Integrated and Sustained Ocean Observations, Ocean.US, was formed in recognition of the requirements of an Integrated Ocean Observing System (IOOS, Malone and Hemsley, this volume). The topic of this contribution is more narrowly focused on improving models through data integration in the larger context of how models are applied and how they interplay with observations. The report from the U.S. Commission on Ocean Policy provides this context, along with conceptual planning documents for the various subsystems of IOOS developed by Ocean.US. Within NOAA, specific guidance on data integration is found in various program planning documents such as the NOAA Annual Guidance Memorandum. The NOAA Storm Surge Partnership Project is an excellent example of a program that is built on the requirement to integrate activities across NOAA, academia, and stakeholders and has a nested data integration activity. Outside of NOAA, but within the IOOS umbrella structure, several regional observing system entities are developing their own tailored data integration activities. Finally, there are a significant number of research activities that are focusing on various assimilation and integration techniques, both for improving and expanding model applications and for optimizing the design of the observing systems themselves. We focus here on current coastal modeling and data integration activities to link existing work to the IOOS construct and goals and to discuss limitations and areas needing improvement.

We present calibration results from Jason-1 (2001–) and TOPEX/POSEIDON (1992–) overflights of a California offshore oil platform (Harvest). Data from Harvest indicate that current Jason-1 sea-surface height (SSH) measurements are high by 138 ± 18 mm. Excepting the bias, the high accuracy of the Jason-1 measurements is in evidence from the overflights. In orbit for over 10 years, the T/P measurement system is well calibrated, and the SSH bias is statistically indistinguishable from zero. Also reviewed are over 10 years of geodetic results from the Harvest experiment.

We present calibration results from Jason-1 (2002-) and TOPEX/Poseidon (1992-) overflights of dedicated verification sites on the Mediterranean island of Corsica and on a California offshore oil platform (Harvest). Harvest served for a decade (1992-2002) as a calibration site for the TOPEX/Poseidon (T/P) mission, and is serving in a similar capacity for Jason-1. Initiated in 1996, the Corsica experiment features a fiducial reference station near Aspretto, and a primary sub-satellite tide-gauge deployment site 40 km south at Cape Senetosa. Both Corsica and Harvest feature carefully designed collocations of space-geodetic and tide-gauge systems to support the absolute calibration of the altimetric sea-surface height (SSH). By incorporating improved estimates of the Jason-1 sea-state bias and columnar atmospheric wet path delay, we observe a bias of about 12 cm.

NOAA has installed two separate water level measurement systems and a suite of ancillary measurement sensors in support of the TOPEX/Poseidon Verification Experiment at Texaco Platform Harvest. The experimental measurement systems are modifications of NOAA's next‐generation water level measurement system (NGWLMS) that is being implemented into the National Water Level Observation Network of the United States. The primary system is configured with a downward looking acoustic water level sensor and the secondary system with a digital "bubbler"; pressure water level sensor (Digibub). The ancillary measurements being made are of barometric pressure, relative humidity, air temperature, water temperature, and water conductivity. Six‐minute interval measurements from each water level sensor and hourly measurements from each ancillary sensor are collected on independent remote terminal units on the platform. The data are transmitted every 3 h via GOES satellite to NOAA for processing in Silver Spring, Maryland. The installation of the measurement systems on the offshore oil platform has required a unique set of elevation corrections that are applied on an operational basis to the water level elevations. These include acoustic sound path air temperature differences for the acoustic data, and water density, nitrogen, and air column corrections to the Digibub data. NOAA field personnel have completed a platform survey in which elevation differences on the platform between the water level sensor "zeros"; and the GPS reference point were established.

This paper investigates correlations between sea level measurements and H 1/3 at Texaco's Platform Harvest. In order to do so, a relationship is shown between the sample standard deviations of the 6‐min NOAA acoustic system measurements and H 1/3 as estimated from CU Paros depth sensors. A transfer function for the NOAA acoustic system is developed by comparison between spectra of 2‐s tsunami mode data with spectra from 1.1‐s pressure data. Part of this transfer function is caused by the decay in pressure effects due to waves between the surface and the orifice of the protective well. The rest is due to damping characteristics of the protective well itself. The transfer function helps show the limitations of using the sample standard deviations of the NOAA acoustic system as a measure of H 1/3 . Differences between sea level measurements show a distinct component related to H 1/3 . The effects related to H 1/3 low‐frequency differences in the measurements, and wave effects are separated using an iterative procedure. If H 1/3 ‐related effects are removed, then the sea level measurements agree to better than 1 cm rms for all three systems. The cause of the low‐frequency differences is not understood. An estimate of the H 1/3 dependence of each individual system is found by removing a 1‐year tidal prediction based on the NOAA acoustic system from sea level from each of the systems. It is assumed that real H 1/3 dependencies in sea level are small. The resulting residuals are iteratively separated as before. These results indicate that the greatest H 1/3 dependence is found in the NOAA Digibub system and the least in the NOAA acoustic system. It should be noted that the H 1/3 dependency found here occurs because of the harsh open ocean conditions at Platform Harvest and would not be expected to be observed under normal conditions in sheltered waters such as harbors, rivers, or lagoons.

Three in situ water level measurement systems have been installed on Platform Harvest in support of the TOPEX/Poseidon Satellite Verification Experiment. Each of the systems have fundamentally different instrument configurations, which provides a unique simultaneous set of measurements in a deep water‐exposed near‐shore environment. Each of the sensor “zeros”; have also been referenced to the same datum as a requirement of the experiment; thus absolute differences can be analyzed. Straightforward, simple comparisons of the systems are presented for TOPEX/Poseidon cycles 2 through 30. The systems are shown to agree well both in the mean and in frequency content. Nontidal sea level residuals are shown to be highly correlated to atmospheric pressure.

The TOPEX/POSEIDON altimeter measurement system is evaluated for the first 46 repeat cycles (September 23, 1992–December 23, 1993) using tracks over the Great Lakes. The temporal variations in lake level are removed from the altimeter measurements using in situ lake level measurements, thus permitting the performance of the altimeter system to be assessed. For the NASA altimeter, the root‐mean‐square (RMS) scatter of the residuals is 3.95 cm using all the tracks over the lakes. However, some of the scatter in this result is probably due to lake tides or seiche, which can amount to a few centimeters amplitude near the ends of the lakes. When the seven best tracks are used, which cross the center of the lakes where tides/seiche effects are minimal, the RMS error is reduced to either 2.9 or 3.0 cm, depending on whether the Centre National d'Etudes Spatiales (CNES) or NASA orbit is used. This places an upper limit on the error budget of the altimeter system, excluding ocean tides and inverse barometer effect. There are several short‐period variations in the residuals. The most pronounced is a 55‐day period, with a 1‐cm amplitude, which we believe is (at least in part) due to orbit error. When the model‐derived wet tropospheric correction is substituted for the TOPEX microwave radiometer correction, the RMS error increases significantly, possibly resulting in an annual cycle of a few centimeters. Evaluation of the ionospheric correction indicates that the dual‐frequency correction provides an average improvement of 0.85 cm over the Doppler orbitography and radiopositioning integrated by satellite (DORIS) correction. Although there are insufficient data to directly assess the CNES altimeter, the relative bias between the altimeters is estimated to be either −14.3 or −15.6 cm (NASA altimeter measuring short), depending on whether the DORIS or dual‐frequency ionospheric correction is applied to the NASA altimeter.

A technique for using satellite radar altimetry data to estimate the temporal variation of the water level in moderate to large lakes and enclosed seas is described. Great Lakes data from the first 2 years of the U.S. Navy's Geosat Exact Repeat Mission (November 1986 to November 1988), for which there is an improved orbit, are used to demonstrate the technique. The Geosat results are compared to the lake level data collected by the Great Lakes Section, National Ocean Service, National Oceanic and Atmospheric Administration, and are found to reproduce the temporal variations of the five major lakes with root‐mean‐square error (rms) ranging from 9.4 to 13.8 cm and a combined average of 11.1 cm. Geosat data are also analyzed for Lake St. Clair, representing a moderate‐sized lake, with a resulting rms of 17.0 cm. During this study period, the water level in the Great Lakes varied in a typical annual cycle of about 0.2 m (0.5 m for Lake Ontario) superimposed on a general decline of approximately 0.5 m. The altimeter data reproduced the general decline reasonably well for all the lakes, but the annual cycle was obscured in some lakes due to systematic errors in the altimeter data. Current and future altimetry missions will have markedly improved accuracy which will permit many moderate (25 km diameter) or larger lakes or enclosed seas to be routinely monitored.