The National Health and Nutrition Examination Survey (NHANES) and the National Health Interview Survey (NHIS) are population-based surveys that have each been linked to administrative data from the Centers for Medicare and Medicaid Services (CMS): the Medicaid Analytic eXtract (MAX) files. These linked data were used to examine, among children under age 18 years, respondent-level concordance be...

A recent highly cited publication, using data from the National Health and Nutrition Examination Survey (NHANES), concluded that the prevalence of childhood hearing loss in the United States is increasing (Shargorodsky, Curan, Curhan, & Eavey, 2010). This article examines the accuracy of that conclusion based on additional data from three nationally-representative surveys of childhood health. U...

Sulphate deposition has decreased by about 60% in the Nordic countries since the early 1980s. Nitrogen deposition has been roughly constant during the past 20 years, with only a minor decrease in the late 1990s. The resulting changes in the chemistry of small lakes have been followed by national monitoring programmes initiated in the 1980s in Finland (163 lakes), Norway (100 lakes) and Sweden (...

The retreat of Arctic summer sea ice has been dramatic in recent years as recorded by satellite images. But it also appears that the thickness of ice has also experienced equally significant shrinkage. Most computer models predict ice-free summer conditions by 2040 to 2100 but real conditions appear to be moving faster than this. The British Catlin Arctic Survey, which got underway in February,...

It is now well documented that over 400 subglacial lakes exist across the bed of the Antarctic Ice Sheet. They comprise a variety of sizes and volumes (from the approx. 250 km long Lake Vostok to bodies of water less than 1 km in length), relate to a number of discrete topographic settings (from those contained within valleys to lakes that reside in broad flat terrain) and exhibit a range of dy...

Shallow lakes, with depths less than ca. 3.5–4 m, are a ubiquitous feature of the Arctic Alaskan Coastal Plain, covering up to 40% of the land surface. With such an extended areal coverage, lakes and their ice regimes represent an important component of the cryosphere. The duration of the ice season has major implications for the regional and local climate, as well as for the physical and bioge...

18 The formation and rapid drainage of supraglacial lakes (SGL) influences the mass balance and 19 dynamics of the Greenland Ice Sheet (GrIS). Although SGLs are expected to spread inland 20 during the 21 century due to atmospheric warming, less is known about their future spatial 21 distribution and volume. We use GrIS surface elevation model and regional climate model 22 outputs to show that a...

The timing of lake ice-out has advanced substantially in many regions of the Northern Hemisphere, however the effects of ice-out timing on lake properties and how they vary regionally remain unclear. Using data from two inter-annual monitoring datasets for a set of three Arctic lakes and one boreal lake, we compared physical, chemical and phytoplankton metrics from two years in which ice-out ti...

A 1-D ice cover model was developed to predict and constrain drivers of long-term ice thickness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface radiative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 a (between 1996 and 2012) of ice thickness changes for the west lobe of Lake Bonney (average ...

We assessed the nutrient (N, P) deficiency of phytoplankton from the perennially ice-covered lakes in Taylor Valley, Antarctica, with 14C-based bioassays. Phytoplankton in the near-surface waters from three of the four lakes displayed elevated photosynthetic carbon assimilation in the presence of added P relative to controls. Carbon assimilation in samples from deep chlorophyll layers was also ...