The Melting Is in the Details Global sea level rises and falls as ice sheets glaciers melt grow, providing an integrated picture of changes volume but little information about how much individual fields are contributing to those variations. Knowing regional structure variability during glaciations deglaciations will clarify mechanisms glacial cycle. Clark et al. (p. 710 ) compiled analyzed more than 5000 radiocarbon cosmogenic surface exposure ages order develop a record maximum extent...

Large millennial-scale fluctuations of the southern margin North American Laurentide Ice Sheet occurred during last deglaciation, when was located between about 43 degrees and 49 N. Fluctuations ice triggered episodic increases in flux freshwater to Atlantic by rerouting continental runoff from Mississippi River drainage Hudson or St. Lawrence Rivers. We found that periods increased flow at same time as reductions formation Deep Water, thus providing a mechanism for observed climate...

Abstract Thermal regimes are fundamental determinants of aquatic ecosystems, which makes description and prediction temperatures critical during a period rapid global change. The advent inexpensive temperature sensors dramatically increased monitoring in recent decades, although most is done by individuals for agency‐specific purposes, collectively these efforts constitute massive distributed sensing array that generates an untapped wealth data. Using the framework provided National...

The imminent demise of montane species is a recurrent theme in the climate change literature, particularly for aquatic that are constrained to networks and elevational rather than latitudinal retreat as temperatures increase. Predictions widespread losses, however, have yet be fulfilled despite decades change, suggesting trends much weaker anticipated may too subtle detection given use sparse water temperature datasets or imprecise surrogates like elevation air temperature. Through...

A physically based eddy diffusion model for simulating the seasonal variation in lake temperature and evaporation is presented validated. Because no lake‐specific fitting of parameters necessary, can be used to simulate studies climate change hydrology a variety settings. The input simple level that applied reconstruct recent fluctuations Harney‐Malheur Lake caused by climatic variations.

A one‐dimensional model of lake temperature, evaporation, and ice has been coupled in an interactive mode with the climate version National Center for Atmospheric Research/Pennsylvania State University regional (mesoscale) atmospheric (MM4). The MM4‐lake makes possible high‐resolution simulations proximity large water bodies. variables required as input are supplied by MM4 simulated values cover axe to model. We have tested system a 60‐day, summertime simulation at Pyramid Lake, Nevada,...

The sensitivity of the tropics to climate change, particularly amplitude glacial‐to‐interglacial changes in sea surface temperature (SST), is one great controversies paleoclimatology. Here we reassess faunal estimates ice age SSTs, focusing on problem no‐analog planktonic foraminiferal assemblages equatorial oceans that confounds both classical transfer function and modern analog methods. A new calibration strategy developed here, which uses past variability species define robust...

A high-resolution, regional climate model nested within a general circulation was used to study the interactions between atmosphere and large Pleistocene lakes in Great Basin of United States. Simulations for January July 18,000 years ago indicate that moisture provided by synoptic-scale atmospheric features primary component hydrologic budgets Lakes Lahontan Bonneville. In addition, lake-generated precipitation substantial budget Lake Bonneville at time. This local lake-atmosphere...

Previous climate model simulations have shown that the configuration of Earth's orbit during early to mid‐Holocene (approximately 10–5 kyr) can account for generally warmer‐than‐present conditions experienced by high latitudes northern hemisphere. New 6 kyr with two atmospheric/mixed‐layer ocean models (Community Climate Model, version 1, CCMl, and Global ENvironmental Ecological Simulation Interactive Systems, 2, GENESIS 2) are presented here compared results from previous 1 were obtained...

This paper describes a set of numerical experiments aimed at evaluating the feasibility applying version National Center for Atmospheric Research-Pennsylvania State University regional model (MM4) to climate simulation over Great Lakes Basin. The objectives this initial modeling investigation are 1) examine whether MM4 can capture primary forcing exerted by on and 2) evaluate what resolution configuration needed simulate such forcing. Simulations region conducted with without representation...

Paleoclimate records from glacial Indian and Pacific oceans sediments document millennial‐scale fluctuations of subsurface dissolved oxygen levels denitrification coherent with North Atlantic temperature oscillations. Yet the mechanism this teleconnection between remote ocean basins remains elusive. Here we present model simulations nitrogen cycles that explain how changes in deepwater subduction can cause large synchronous variations minimum zones throughout Northern Hemisphere oceans,...

We have completed an array of high-resolution simulations present and future climate over Western North America (WNA) Eastern (ENA) by dynamically downscaling global using a regional model, RegCM3. The are intended to provide long time series internally consistent surface atmospheric variables for use in climate-related research. In addition providing weather data the past, present, future, we developed integrated flow methodology processing, summarizing, viewing, delivering datasets wide...

ABSTRACT Bioclimatic models predict large reductions in native trout across the Rocky Mountains 21st century but lack details about how changes will occur. Through five case histories region, we explore a changing climate has been affecting streams and potential consequences for trout. Monitoring records show trends temperature hydrographs consistent with warming recent decades. Biological implications include upstream shifts thermal habitats, risk of egg scour, increased wildfire...

Before coupled atmosphere‐lake models can be used to study the response of large lake systems climatic forcings, we must first evaluate how well they simulate water balance and associated atmosphere interactions under present‐day conditions. We hydrology simulated by a model NCAR's regional climate (RegCM2) in Aral Sea. The meteorological variables that are input RegCM2. Simulated surface air temperatures closely match observed values, except during spring fall when too cold. magnitude...

We have developed a physically based, distributed surface energy balance model to simulate glacier mass under meteorological and climatological forcing. Here we apply the estimate summer ablation on South Cascade Glacier, Washington, for 2004 2005 seasons. To arrive at optimal simulations, investigate quantify uncertainty associated with selecting from range of physical parameter values that are not commonly measured in glaciological field studies. optimize performance by varying atmospheric...

Part of the East Antarctic Ice Sheet advanced and retreated in synchrony with Northern Hemispheric ice sheets.

We combine large observed data sets and dynamically downscaled climate to explore historic future (2050-2069) stream temperature changes over the topographically diverse Greater Yellowstone Ecosystem (elevation range = 824-4017 m). link temperatures with fish growth models investigate how changing thermal regimes could influence distribution persistence of native cutthroat trout (YCT) competing invasive species. find that during recent decade (2000-2009) surpass anomalously warm period...

Abstract. We apply GENMOM, a coupled atmosphere–ocean climate model, to simulate eight equilibrium time slices at 3000-year intervals for the past 21 000 years forced by changes in Earth–Sun geometry, atmospheric greenhouse gases (GHGs), continental ice sheets, and sea level. Simulated global cooling during Last Glacial Maximum (LGM) is 3.8 °C rate of post-glacial warming overall agreement with recently published temperature reconstructions. The greatest occurs between 15 12 ka (2.4 over...