Sentences with phrase «estimating mean sea»

A recent Ph.D thesis by Phil Watson of the University of New South Wales (LINK) developed improved techniques to estimate mean sea level velocity and acceleration from long ocean water level time series.

Not exact matches

The absence of crustal deformation from Tharsis means the seas would have been shallower, holding about half the water of earlier estimates.

«The tide gauge measurements are essential for determining the uncertainty in the GMSL (global mean sea level) acceleration estimate,» said co-author Gary Mitchum, USF College of Marine Science.

The estimated DJFM Antarctic sea ice extent climatology for the period 1897 — 1917, with and without the inclusion of the Worby and Comiso offset (an offset between where satellites and human observers view the sea ice edge), is plotted alongside time series of DJFM mean sea ice extent calculated from HadISST2.2, NASA Team and NASA Bootstrap sea ice datasets.

It bears noting that even if the SEA mean estimate were correct, it still lies well above the ever - more implausible estimates of those that wish the climate sensitivity were negligible.

The theoretical mean sea level (or theoretical mean water, MW) is an estimate for the long - term mean value (more precisely, expectation value) of sea level, made for practical purposes.

Curiously, the mean SEA estimate (2.4 ºC) is identical to the mean KEA number, but there is a big difference in what they concluded the mean temperature at the LGM was,....

But what exactly the new findings mean for sea level rise estimates is still unknown.

B. Takes an adjustment to sea temperatures in a defined period and implies that it impacts the global mean temperatures trend estimates over the entire twentieth century.

In the paper these factors are estimated and it is concluded that the North Carolina curve should be within about 10 cm of global mean sea level.

Which means all estimates on sea level rise have a large unknown fudge factor missing.

The same holds for the specific global mean EIV temperature reconstruction used in the present study as shown in the graph below (interestingly, eliminating the proxies in question actually makes the reconstruction overall slightly cooler prior to AD 1000, which — as noted in the article — would actually bring the semi-empirical sea level estimate into closer agreement with the sea level reconstruction prior to AD 1000).

We stress that no - one (and we mean no - one) has published an informed estimate of more than 2 meters of sea level rise by 2100.

However, the CRU global mean combined land air / sea surface temperature estimates for Jan - Aug 2005 lag behind the 1998 annual mean estimate by 0.08 C (0.50 C vs. 58C for 1998) while GISS indicates a lag of 0.02 C.

> A new comment on the post # 74 «Michael Crichton's State of Confusion» is > waiting for your approval > > Author: Hans Erren -LRB--RRB- > E-mail: erren21 @... > URL: > Whois:... > Comment: > Sea - level rise > > Although satellite data (TOPEX / POSEIDON (sic) and JASON) shows a much > steeper trend over recent years (2.8 mm / yr) than the long term mean > estimates from tide gauges (1.7 to 2.4 mm / yr), each method compared to > itself does not indicate an accelleration.

Kauker et al. (AWI / OASys), 5.58 (+ / - 0.41), Modeling (same as June) We estimate a monthly mean September sea - ice extent of 5.67 ± 0.40 million km2 (without assimilation of sea - ice / ocean observations).

The results of the analysis demonstrate that relative to the reference case, projected atmospheric CO2 concentrations are estimated by 2100 to be reduced by 3.29 to 3.68 part per million by volume (ppmv), global mean temperature is estimated to be reduced by 0.0076 to 0.0184 °C, and sea - level rise is projected to be reduced by approximately 0.074 — 0.166 cm, based on a range of climate sensitivities.

«The global mean sea level for the period January 1900 to December 2006 is estimated to rise at a rate of 1.56 ± 0.25 mm / yr which is reasonably consistent with earlier estimates, but we do not find significant acceleration»

Several other satellite altimeters have also been launched, and the data from these have been used to estimate global mean sea level trends since 1993.

Its estimated ice volume and contribution to mean global sea level reside well within their ranges of natural variability, and from the current looks of things, they are not likely to depart from those ranges any time soon.

The theoretical mean sea level (or theoretical mean water, MW) is an estimate for the long - term mean value (more precisely, expectation value) of sea level, made for practical purposes.

Since 1950, global mean sea surface temperatures have risen roughly 1 ° F (0.6 ° C).6 Scientists estimate that regional sea surface temperatures in the North Sea increased by 1.6 ° F (0.9 ° C) from 1958 to 200sea surface temperatures have risen roughly 1 ° F (0.6 ° C).6 Scientists estimate that regional sea surface temperatures in the North Sea increased by 1.6 ° F (0.9 ° C) from 1958 to 200sea surface temperatures in the North Sea increased by 1.6 ° F (0.9 ° C) from 1958 to 200Sea increased by 1.6 ° F (0.9 ° C) from 1958 to 2002.7

«Trends and acceleration in global and regional sea levels since 1807» «Evaluation of the global mean sea level budget between 1993 and 2014» «Considerations for estimating the 20th century trend in global mean sea level» «New estimate of the current rate of sea level rise from a sea level budget approach» «Reassessment of 20th century global mean sea level rise» «The increasing rate of global mean sea - level rise during 1993 — 2014» «Unabated global mean sea - level rise over the satellite altimeter era» «An increase in the rate of global mean sea level rise since 2010»

J. T. Fasullo, R. S. Nerem & B. Hamlington Scientific Reports 6, Article number: 31245 (2016) doi: 10.1038 / srep31245 Download Citation Climate and Earth system modellingProjection and prediction Received: 13 April 2016 Accepted: 15 July 2016 Published online: 10 August 2016 Erratum: 10 November 2016 Updated online 10 November 2016 Abstract Global mean sea level rise estimated from satellite altimetry provides a strong constraint on climate variability and change and is expected to accelerate as the rates of both ocean warming and cryospheric mass loss increase over time.

Figure 3: «Considerations for estimating the 20th century trend in global mean sea level» Figure 1B: «Reassessment of 20th century global mean sea level rise» «Recent global sea level acceleration started over 200 years ago?»

Abstract: «Global mean sea level rise estimated from satellite altimetry provides a strong constraint on climate variability and change and is expected to accelerate as the rates of both ocean warming and cryospheric mass loss increase over time.

The mean estimates for the 2010 September Sea Ice Outlook based on May, June, and July data were close to the observed value with a rather small quartile distribution (as a measure of deviation from the mean).

«It is likely that the rate of global mean sea level rise has continued to increase since the early 20th century, with estimates that range from 0.000 -LSB--- 0.002 to 0.002] mm yr — 2 to 0.013 [0.007 to 0.019] mm yr — 2.

Kauker et al (Alfred Wegener Institute [AWI], Ocean Atmosphere Systems [OASys]-RRB-, 3.95 (± 0.39), Modeling We estimate a monthly mean September sea - ice extent of 3.95 ± 0.39 million km2.

An independent estimate of global - mean evaporation provides additional support, but critical assumptions on relative humidity and the air - sea temperature difference changes are made that do not have adequate observational basis and are inconsistent with climate models.»

Assuming a full - glacial temperature lapse rate of -6 °C / 1000m, depression of mean annual temperature in glaciated alpine areas was ca 5.4 ± 0.8 °C; it is similar to values of temperature depression (5 - 6.4 °C) for the last glaciation obtained from various terrestrial sites, but contrasts with tropical sea - surface temperature estimates that are only 1 - 3 °C cooler than present.

All of these characteristics (except for the ocean temperature) have been used in SAR and TAR IPCC (Houghton et al. 1996; 2001) reports for model - data inter-comparison: we considered as tolerable the following intervals for the annual means of the following climate characteristics which encompass corresponding empirical estimates: global SAT 13.1 — 14.1 °C (Jones et al. 1999); area of sea ice in the Northern Hemisphere 6 — 14 mil km2 and in the Southern Hemisphere 6 — 18 mil km2 (Cavalieri et al. 2003); total precipitation rate 2.45 — 3.05 mm / day (Legates 1995); maximum Atlantic northward heat transport 0.5 — 1.5 PW (Ganachaud and Wunsch 2003); maximum of North Atlantic meridional overturning stream function 15 — 25 Sv (Talley et al. 2003), volume averaged ocean temperature 3 — 5 °C (Levitus 1982).

A policymaker will take this as meaning that sea level rise is probably going to be less than a meter even if CO2 increases to 936 ppm, in other words, policymakers will take this «objective stuff» as serious, reliable estimates of what to expect.

The uncertainty in the global mean sea level trend is estimated to be of ± 0.5 mm / yr in a confidence interval of 90 % (1.65 sigma), whereas the uncertainty of the regional mean sea level trends is of the order of 2 - 3 mm / yr with values as low as 0.5 mm / yr or as high as 5.0 mm / yr depending on the region considered (Legeais et al., 2018, under review).

The mean sea level evolution estimated in the global ocean is derived from box - averaged gridded sea level maps weighted by the cosine of the latitude.

AWI Consortium (Kauker et al.), 4.32 (± 0.30), Modeling (ice - ocean) We estimate a monthly mean September sea - ice extent of 4.32 + - 0.30 million km2.

Wang, 6.31 (5.84 - 6.78), Modeling The projected Arctic sea ice extent from CPC based on NCEP ensemble mean CFSv2 forecast is 6.31 × 106 km2 with an estimated error of ± 0.47 × 106 km2.

Among other things, this means that the IPCC team, which did not have the ice melt data through the 1990s, will need to revise upward its projected rise in sea level for this century — currently estimated to range from 0.09 meters to 0.88 meters (from 4 to 35 inches).

However, Figure 2 of Cowtan et al 2015 shows, based on essentially the same set of CMIP5 RCP8.5 simulations as REA16 and excluding sea - ice related effects, a mean differential of ~ 5 % (range 1 % — 7 %), over double the 2 % I estimate.

In addition, land stations are allowed to provide temperature estimates for ocean cells where no sea surface temperature is available - in practice, this means that coastal stations around the Arctic provide temperature readings for the pole.

We compare simulation cooling from the combined forcing to a GMT reconstruction, based on a global mean sea surface temperature reconstruction (43) that we scaled by the factor 1.84 so as to match estimated LGM cooling (ref.

This task involved extensive time series analysis that identified Singular Spectrum Analysis (SSA) as an optimal analytic for resolving estimates of mean sea level from long tide gauge records with improved accuracy and temporal resolution, since it provides a superior capability to separate key time varying harmonic components of the time series.

We received 21 responses with a range of estimates from 4.0 to 5.0 million square kilometers for the September 2012 arctic mean sea ice extent (Figure 1).

One could choose to look at the global mean sea level instead, which does have a physical meaning because it represents an estimate for the volume of the water in the oceans, but the choice is not crucial as long as the indicator used really responds to the conditions under investigation.

However, ocean temperatures have warmed almost everywhere on the planet, with 0.5 ºC being the global mean rise of sea surface temperature, hence Trenberth's reasonable estimate that this much is the contribution from global forcings like CO2.

Using a 25 - y time series of precision satellite altimeter data from TOPEX / Poseidon, Jason - 1, Jason - 2, and Jason - 3, we estimate the climate - change — driven acceleration of global mean sea level over the last 25 y to be 0.084 ± 0.025 mm / y2.

I don't know what «benchmark island» means, but the current best estimate of the rate of sea - level rise, averaged over the world during 2003 to 2008, is +2.5 millimetres / yr, give or take 0.4 mm.

... Averaged over the global ocean surface, the mean rate of sea level change due to GIA is independently estimated from models at -0.3 mm / yr (Peltier, 2001, 2002, 2009; Peltier & Luthcke, 2009).

To obtain an estimate, a sea ice area from the Arctic Basin (excluding the pole and the multiyear sea ice north of Greenland) is regressed with the previous years and their September mean extents.

We received 21 responses for the Pan-Arctic report (Figure 1), with estimates in the range of just below 4.0 million square kilometers to as high as 5.4 million square kilometers for the September arctic mean sea ice extent.