scholarly journals Ice Forecasting in the Next-Generation Great Lakes Operational Forecast System (GLOFS)

2018 ◽  
Vol 6 (4) ◽  
pp. 123 ◽  
Author(s):  
Eric Anderson ◽  
Ayumi Fujisaki-Manome ◽  
James Kessler ◽  
Gregory Lang ◽  
Philip Chu ◽  
...  
Keyword(s):  
Great Lakes ◽  
Ice Cover ◽  
State Variables ◽  
Next Generation ◽  
Forecast System ◽  
Modeling Framework ◽  
Operational Forecast ◽  
Lake Ecology ◽  
Ice Conditions ◽  
Forecast Guidance

Ice Cover in the Great Lakes has significant impacts on regional weather, economy, lake ecology, and human safety. However, forecast guidance for the lakes is largely focused on the ice-free season and associated state variables (currents, water temperatures, etc.) A coupled lake-ice model is proposed with potential to provide valuable information to stakeholders and society at large about the current and near-future state of Great Lakes Ice. The model is run for three of the five Great Lakes for prior years and the modeled ice cover is compared to observations via several skill metrics. Model hindcasts of ice conditions reveal reasonable simulation of year-to-year variability of ice extent, ice season duration, and spatial distribution, though some years appear to be prone to higher error. This modeling framework will serve as the basis for NOAA’s next-generation Great Lakes Operational Forecast System (GLOFS); a set of 3-D lake circulation forecast modeling systems which provides forecast guidance out to 120 h.

Development, implementation, and skill assessment of the NOAA/NOS Great Lakes Operational Forecast System

2011 ◽  
Vol 61 (9) ◽  
pp. 1305-1316 ◽  
Author(s):  
Philip Y. Chu ◽  
John G. W. Kelley ◽  
Gregory V. Mott ◽  
Aijun Zhang ◽  
Gregory A. Lang
Keyword(s):  
Great Lakes ◽  
Skill Assessment ◽  
Forecast System ◽  
Operational Forecast

scholarly journals Severe Ice Conditions in the Bohai Sea, China, and Mild Ice Conditions in the Great Lakes during the 2009/10 Winter: Links to El Niño and a Strong Negative Arctic Oscillation

2011 ◽  
Vol 50 (9) ◽  
pp. 1922-1935 ◽  
Author(s):  
Xuezhi Bai ◽  
Jia Wang ◽  
Qinzheng Liu ◽  
Dongxiao Wang ◽  
Yu Liu
Keyword(s):  
North America ◽  
Great Lakes ◽  
El Niño ◽  
Arctic Oscillation ◽  
Bohai Sea ◽  
El Nino ◽  
Ice Cover ◽  
The Bohai Sea ◽  
El Niño Event ◽  
Ice Conditions

AbstractThis study investigates the causes of severe ice conditions over the Bohai Sea, China, and mild ice cover over the North American Great Lakes under the same hemispheric climate patterns during the 2009/10 winter with a strong negative Arctic Oscillation (AO) and an El Niño event. The main cause of severe ice cover over the Bohai Sea was the strong negative AO. Six of seven winters with severe ice were associated with a strong negative AO during the period 1954–2010. The Siberian high (SH) in the 2009/10 winter was close to normal. The influence of El Niño on the Bohai Sea was not significant. In contrast, the mild ice conditions in the Great Lakes were mainly caused by the strong El Niño event. Although the negative AO generally produces significant colder surface air temperature (SAT) and heavy ice cover over the Great Lakes, when it coincided with a strong El Niño event during the 2009/10 winter the El Niño–induced Pacific–North America (PNA)-like pattern dominated the midlatitudes and was responsible for the flattening of the ridge–trough system over North America, leading to warmer-than-normal temperatures and mild ice conditions over the Great Lakes. This comparative study revealed that interannual variability of SAT in North America, including the Great Lakes, is effectively influenced by El Niño events through a PNA or PNA-like pattern whereas the interannual variability of SAT in northeastern China, including the Bohai Sea area, was mainly controlled by AO and SH.

Atmospheric teleconnection patterns associated with severe and mild ice cover on the Great Lakes, 1963–2011

2012 ◽  
Vol 47 (3-4) ◽  
pp. 421-435 ◽  
Author(s):  
Xuezhi Bai ◽  
Jia Wang
Keyword(s):  
North America ◽  
Great Lakes ◽  
El Niño ◽  
El Nino ◽  
Ice Cover ◽  
Reanalysis Data ◽  
Teleconnection Pattern ◽  
La Niña ◽  
Atmospheric Teleconnection ◽  
La Nina

Atmospheric teleconnection circulation patterns associated with severe and mild ice cover over the Great Lakes are investigated using the composite analysis of lake ice data and National Center of Environmental Prediction (NCEP) reanalysis data for the period 1963–2011. The teleconnection pattern associated with the severe ice cover is the combination of a negative North Atlantic Oscillation (NAO) or Arctic Oscillation (AO) and negative phase of Pacific/North America (PNA) pattern, while the pattern associated with the mild ice cover is the combination of a positive PNA (or an El Niño) and a positive phase of the NAO/AO. These two extreme ice conditions are associated with the North American ridge–trough variations. The intensified ridge–trough system produces a strong northwest-to-southeast tilted ridge and trough and increases the anomalous northwesterly wind, advecting cold, dry Arctic air to the Great Lakes. The weakened ridge–trough system produces a flattened ridge and trough, and promotes a climatological westerly wind, advecting warm, dry air from western North America to the Great Lakes. Although ice cover for all the individual lakes responds roughly linearly and symmetrically to both phases of the NAO/AO, and roughly nonlinearly and asymmetrically to El Niño and La Niña events, the overall ice cover response to individual NAO/AO or Niño3.4 index is not statistically significant. The combined NAO/AO and Niño3.4 indices can be used to reliably project severe ice cover during the simultaneous –NAO/AO and La Niña events, and mild ice cover during the simultaneous +NAO/AO and El Niño events.

A record-breaking low ice cover over the Great Lakes during winter 2011/2012: combined effects of a strong positive NAO and La Niña

2014 ◽  
Vol 44 (5-6) ◽  
pp. 1187-1213 ◽  
Author(s):  
Xuezhi Bai ◽  
Jia Wang ◽  
Jay Austin ◽  
David J. Schwab ◽  
Raymond Assel ◽  
...  
Keyword(s):  
Great Lakes ◽  
Ice Cover ◽  
La Niña ◽  
Combined Effects ◽  
La Nina

scholarly journals Towards the Development of an Operational Forecast System for the Florida Coast

2017 ◽  
Vol 5 (1) ◽  
pp. 8 ◽  
Author(s):  
Vladimir Paramygin ◽  
Y. Sheng ◽  
Justin Davis
Keyword(s):  
Forecast System ◽  
Operational Forecast

scholarly journals Marine boundary layer cloud regimes and POC formation in a CRM coupled to a bulk aerosol scheme

2013 ◽  
Vol 13 (24) ◽  
pp. 12549-12572 ◽  
Author(s):  
A. H. Berner ◽  
C. S. Bretherton ◽  
R. Wood ◽  
A. Muhlbauer
Keyword(s):  
Boundary Layer ◽  
Marine Boundary Layer ◽  
Three Dimensional ◽  
Two Dimensional ◽  
State Variables ◽  
Liquid Water Path ◽  
Modeling Framework ◽  
Boundary Layer Cloud ◽  
Cloud Regimes ◽  
Layer Cloud

Abstract. A cloud-resolving model (CRM) coupled to a new intermediate-complexity bulk aerosol scheme is used to study aerosol–boundary-layer–cloud–precipitation interactions and the development of pockets of open cells (POCs) in subtropical stratocumulus cloud layers. The aerosol scheme prognoses mass and number concentration of a single lognormal accumulation mode with surface and entrainment sources, evolving subject to processing of activated aerosol and scavenging of dry aerosol by clouds and rain. The CRM with the aerosol scheme is applied to a range of steadily forced cases idealized from a well-observed POC. The long-term system evolution is explored with extended two-dimensional (2-D) simulations of up to 20 days, mostly with diurnally averaged insolation and 24 km wide domains, and one 10 day three-dimensional (3-D) simulation. Both 2-D and 3-D simulations support the Baker–Charlson hypothesis of two distinct aerosol–cloud "regimes" (deep/high-aerosol/non-drizzling and shallow/low-aerosol/drizzling) that persist for days; transitions between these regimes, driven by either precipitation scavenging or aerosol entrainment from the free-troposphere (FT), occur on a timescale of ten hours. The system is analyzed using a two-dimensional phase plane with inversion height and boundary layer average aerosol concentrations as state variables; depending on the specified subsidence rate and availability of FT aerosol, these regimes are either stable equilibria or distinct legs of a slow limit cycle. The same steadily forced modeling framework is applied to the coupled development and evolution of a POC and the surrounding overcast boundary layer in a larger 192 km wide domain. An initial 50% aerosol reduction is applied to half of the model domain. This has little effect until the stratocumulus thickens enough to drizzle, at which time the low-aerosol portion transitions into open-cell convection, forming a POC. Reduced entrainment in the POC induces a negative feedback between the areal fraction covered by the POC and boundary layer depth changes. This stabilizes the system by controlling liquid water path and precipitation sinks of aerosol number in the overcast region, while also preventing boundary layer collapse within the POC, allowing the POC and overcast to coexist indefinitely in a quasi-steady equilibrium.

scholarly journals Description and Analysis of a 20-Year (1960-79) Digital Ice-Concentration Database for the Great Lakes of North America

1983 ◽  
Vol 4 ◽  
pp. 14-18 ◽  
Author(s):  
Raymond A. Assel
Keyword(s):  
North America ◽  
Great Lakes ◽  
Surface Area ◽  
Information Service ◽  
Grid Cell ◽  
Ice Cover ◽  
Unit Surface Area ◽  
Grid Cells ◽  
Data Set ◽  
Ice Concentration

A digital ice-concentration database spanning 20 years (1960 to 1979) was established for the Great Lakes of North America. Data on ice concentration, i.e. the percentage of a unit surface area of the lake that is ice-covered, were abstracted from over 2 800 historic ice charts produced by United States and Canadian government agencies. The database consists of ice concentrations ranging from zero to 100% in 10% increments for individual grid cells of size 5 × 5 km constituting the surface area of each Great Lake. The data set for each of the Great Lakes was divided into half-month periods for statistical analysis. Maxinium, minimum, median, mode, and average ice-concentrations statistics were calculated for each grid cell and half-month period. A lakewide average value was then calculated for each of the half-month ice-concentration statistics for all grid cells for a given lake. Ice-cover variability and the normal extent and progression of the ice cover is discussed within the context of the lakewide averaged value of the minimum and maximum ice concentrations and the lakewide averaged value of the median ice concentrations, respectively. Differences in ice-cover variability among the five Great Lakes are related to mean lake depth and accumulated freezing degree-days. A Great Lakes ice atlas presenting a series of ice charts which depict the maximum, minimum, and median icecover concentrations for each of the Great Lakes for nine half-monthly periods, starting the last half of December and continuing through the last half of April will be published in 1983 by the National Oceanic and Atmospheric Administration (NOAA). The database will be archived at the National Snow and Ice Data Center of the National Environmental Satellite Data and Information Service (NESDIS) in Boulder, Colorado, USA, also in 1983.

scholarly journals Seasonal and interannual changes of ice massifs in East Siberian sea

2018 ◽  
Vol 64 (3) ◽  
pp. 229-240 ◽  
Author(s):  
A. V. Yulin ◽  
M. V. Sharatunova ◽  
E. A. Pavlova ◽  
V. V. Ivanov
Keyword(s):  
Interannual Variability ◽  
20Th Century ◽  
Autonomous Navigation ◽  
Ice Cover ◽  
Cold Period ◽  
Main Difficulty ◽  
East Siberian Sea ◽  
Climatic Period ◽  
Fast Decrease ◽  
Ice Conditions

The paper considers the seasonal and interannual variability of the Novosibirsky and Ayonsky ice massifs of the East Siberian Sea, which represent the main difficulty for navigation during summer.Analysis of ice conditions showed the tendency towards the onset of a new climatic period - “relative warming”. This is consistent with the regional quasi-periodic 30-year alternations beetween the “relatively cold” and “relatively warm” climatic periods identified in the AARI.We have compared ice conditions of the “relatively cold” period of 1958–1987 and the “relatively warm” period of 1988–2017. Since the end of the 1980s the ice massifs began to decrease more intensively with the onset of break up some 10–20 days earlier.In general, the drift ice area during  summer has decreased by 15–20 % in the western part of the sea and by 20–30 % in eastern one. The fast decrease of close floatingice in the East Siberian Sea observed in the last decades resulted in increase of the possibilities of autonomous navigation.The latest works containing the analysis of in conditions of the East Siberian Sea belong to the 90s of last century. In these works ice conditions of the period of the 40–80s of the 20th century were considered. During this period, the background of the ice cover extent was high. As a result, the usage of the average values of ice massifs areas calculated on all observations series (since 1946), is not informative for characterizing ice conditions during separately taken periods.

Modeling framework to estimate spawning and hatching locations of pelagically spawned eggs

2019 ◽  
Vol 76 (4) ◽  
pp. 597-607 ◽  
Author(s):  
Holly S. Embke ◽  
Patrick M. Kocovsky ◽  
Tatiana Garcia ◽  
Christine M. Mayer ◽  
Song S. Qian
Keyword(s):  
Great Lakes ◽  
Field Data ◽  
Ctenopharyngodon Idella ◽  
Native Range ◽  
Invasive Fish ◽  
Modeling Framework ◽  
Hydraulic Models ◽  
Successful Recruitment ◽  
Grass Carp Ctenopharyngodon Idella ◽  
Spawning Sites

Identifying spawning and hatching locations is vital to controlling invasive fish and conserving imperiled fish, which can be difficult for pelagically spawning species with semi-buoyant eggs. In freshwater systems, this reproductive strategy is common among cyprinid species, such as Chinese carp species currently threatening the Great Lakes. Following the confirmation that one of these species, grass carp (Ctenopharyngodon idella), was spawning in a Great Lakes tributary, we developed a modeling framework to combine field data with hydraulic models to calculate the most probable spawning and hatching locations for collected eggs. Our results indicate that the estimated spawning location encompassed habitat consistent with spawning sites in grass carp’s native range. Additionally, all eggs were identified to have hatched in the river, increasing the likelihood of successful recruitment. This modeling framework can be used to estimate spawning and hatching locations for Chinese carp species, as well as all pelagic, riverine spawners. Spawning and hatching locations provide key information to researchers about the reproductive requirements of species and to agencies about how best to manage populations for control or restoration.

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