Sentences with phrase «sea ice conditions using»

The Sea Ice Index relies on NASA - developed methods to estimate sea ice conditions using passive - microwave data from the Defense Meteorological Satellite Program (DMSP) the Special Sensor Microwave Imager / Sounder (SSMIS).

Not exact matches

[Andy Revkin — The model runs used by the U.S. Geological Survey's Steven Amstrup to project sea ice conditions midcentury onward all presumed carbon dioxide concentrations continue to rise.

Arbetter, 4.7, Statistical A statistical model using regional observations of sea ice area and global NCEP air temperature, sea level pressure, and freezing degree day estimates continues the trend of projecting below - average summer sea ice conditions for the Arctic.

This month's report includes details on the causes of the 2012 minimum, the use of sea ice volume versus extent, sea ice in climate models, and late spring 2013 conditions.

«Using a GCM, can we regenerate the land temperature record from the ocean record using observed SSTs and sea ice distribution as a boundary condiUsing a GCM, can we regenerate the land temperature record from the ocean record using observed SSTs and sea ice distribution as a boundary condiusing observed SSTs and sea ice distribution as a boundary condition?

On the other side of the Arctic, Russian martime operations using icebreakers on the Northern Sea Route began in 1932 and give no evidence for improving ice conditions in this period; rather the opposite, as 1937 and 1940 were noted for heavy ice in the Laptev Sea.

The new system — which captures current sea - ice conditions more accurately and in greater detail by blending several streams of data — has been used operationally in Navy forecasting since February, Posey said.

The ARISE campaign, using NASA's C - 130 Hercules aircraft from Wallops Flight Facility in Virginia, had its first science flight on Sept. 4 and has already carried out several surveys of sea ice and cloud conditions.

A regression - based forecast for September ice extent around Svalbard (an area extending from 72 — 85N and 0 — 40E), which uses May sea surface temperatures, the March index of the Arctic Oscillation, and April ice conditions as predictors, yielded a mean ice extent in September 2010 of 255,788 square kilometers around Svalbard.

This is substantially lower than the earlier estimates, reflecting both lower than average sea ice extent used as initial conditions this summer and a persistent downward trend in sea ice extent over the past decade (and longer).

We also make use of two lengthy control simulations conducted with CESM1 under constant 1850 radiative conditions: a 2200 - year control run using the fully - coupled configuration (hereafter termed the «coupled control run»), and a 2600 - year control run using only the atmospheric model component coupled to the land model component from CESM1 with a specified repeating seasonal cycle of sea surface temperatures (SSTs) and sea ice conditions taken from the long - term climatology of the fully - coupled control run (hereafter termed the «atmospheric control run»).

The ensemble consists of seven members each of which uses a unique set of NCEP / NCAR atmospheric forcing fields from recent years, representing recent climate, such that ensemble member 1 uses 2005 NCEP / NCAR forcing, member 2 uses 2006 forcing..., and member 7 uses 2011 forcing... In addition, the recently available IceBridge and helicopter - based electromagnetic (HEM) ice thickness quicklook data are assimilated into the initial 12 - category sea ice thickness distribution fields in order to improve the initial conditions for the predictions.

Arbetter, 4.0, n / a, Statistical (updated 13 August) Using conditions from week 30 of 2012 (ie August 1, 2012), a revised minimum Arctic sea ice extent of 4.03 million km2 is projected for the week of September 7, 2012.

On 27 June 2008 a request was issued to the arctic research community requesting input for the June 2008 Outlook Report on arctic sea ice conditions for September 2008, to update the May Outlook using June data.

A smaller multiyear ice area in the Arctic Ocean means that the sea ice summer extent is more sensitive to weather conditions during summer and thus more difficult to predict using statistical regression analysis since seasonal weather forecasts are not reliable.

However, the ensemble mean September 2008 sea ice conditions, using the range of historical summer weather, gives a value of sea ice extent that is slightly more than 2007.

To obtain the «best possible» initial ice - ocean conditions for the forecasts, we conducted a retrospective simulation using PIOMAS that assimilates satellite ice concentration and sea surface temperature data.

Our projected Arctic sea ice extent from the NCEP CFSv2 model with June 2013 revised - initial condition using 30 - member ensemble forecast is (surprisingly increased to) 4.7 million square kilometers with a standard deviation of 0.4 million square kilometers.

Proxy data such as those generated from ice core samples, measurements of tree rings intervals, bore samples taken from sediments from the ocean and sea floor, and measurement of gases from bubbles trapped in ice are some examples of preserved physical characteristics of the past used by scientists to reconstruct prevailing climatic conditions in the past.

As with previous CIS contributions, the 2016 forecast was derived by considering a combination of methods: 1) a qualitative heuristic method based on observed end - of - winter Arctic ice thickness / extent, as well as winter surface air temperature, spring ice conditions and the summer temperature forecast; 2) a simple statistical method, Optimal Filtering Based Model (OFBM), that uses an optimal linear data filter to extrapolate the September sea ice extent time - series into the future and 3) a Multiple Linear Regression (MLR) prediction system that tests ocean, atmosphere and sea ice predictors.

The second method uses a optimal filtering based statistical model, and the third estimate is based on regression models relating September sea ice extent to spring atmospheric and oceanic conditions.

When scientists compare average sea ice conditions between years, they often use a 30 - year reference period of 1981 to 2010.

Because Arctic sea ice is influenced by both air and water temperatures, the study authors use a combination of Arctic ice core, tree - ring and lake sediments to reconstruct Arctic conditions over the last 2,000 years.

In their paper «Exploring recent trends in Northern Hemisphere blocking,» Barnes and colleagues used various meteorological definitions of «blocking» along with various datasets of atmospheric conditions to assess whether or not there have been any trends in the frequency of blocking events that could be tied to changes in global warming and / or the declines in Arctic sea ice.

«Polar bears are sticking to using the same type of habitat conditions even while sea ice disappears,» says lead author Ryan Wilson of the U.S. Fish and Wildlife Service.

For the «2013 as observed» experiment, the atmospheric model uses observed sea surface temperature data from December 2012 to November 2013 from the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) dataset (Stark et al. 2007; Donlon et al. 2012) and present day atmospheric gas concentrations to simulate weather events that are possible given the observed climate conditiosea surface temperature data from December 2012 to November 2013 from the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) dataset (Stark et al. 2007; Donlon et al. 2012) and present day atmospheric gas concentrations to simulate weather events that are possible given the observed climate conditioSea Surface Temperature and Sea Ice Analysis (OSTIA) dataset (Stark et al. 2007; Donlon et al. 2012) and present day atmospheric gas concentrations to simulate weather events that are possible given the observed climate conditioSea Ice Analysis (OSTIA) dataset (Stark et al. 2007; Donlon et al. 2012) and present day atmospheric gas concentrations to simulate weather events that are possible given the observed climate conditions.

Using a model that tracked a range of habitat conditions, including water temperature and depth from sea ice, to predict which habitats would be most impacted by climate change, William Cheung, the study's lead author, and his colleagues found that around 50 species of commercial fishes living near or at the poles will go extinct within the next 4 decades.

They also ran atmospheric models that used observed global sea surface temperatures, Arctic sea ice conditions and atmospheric carbon dioxide concentrations in 2010 to assess whether such factors might have contributed to the heat wave.

However, scientists have used historical records of sea ice conditions to estimate sea ice extent before 1979.

The passive - microwave data used for the Sea Ice Index is especially helpful because the sensor can «see» through clouds and deliver data even during the six months of Arctic darkness and frequently cloudy conditions.

While several August Outlooks did not change from the July Outlook, forecasts using statistical techniques together with end of July sea ice conditions tended to show slightly lower estimates for the September minimum compared to the previous outlook (e.g. Meier et al.; Beitsch et al.; Lukovich et al.; Randles).

Or, to understand the causes of melting sea - ice or severe drought, researchers can use sophisticated climate models to help identify — and potentially isolate — various factors that could individually contribute or dynamically interact to influence climate conditions in a particular region,» he says.