Rise is due to both melting ice and the thermal
expansion of warming ocean waters.
To know what these high numbers mean for local changes on the world's coastlines, you need a framework that accounts for all the key drivers: among them not just Antarctica, but also Greenland, mountain glaciers,
the expansion of the warming ocean, changes in winds and current, shifts in Earth's gravitational field, and land motion.
The latest estimates for sea level rise cited by the International Panel on Climate Change (IPCC) are based largely on the melting of nonpolar glaciers and
the expansion of warmer ocean waters.
In fact, the IPCC gets most of its prjected sea rise from thermal
expansion of warmer oceans, not from ice melting.
But to slow sea level increases — which are caused primarily by melting glaciers and
the expansion of warming oceans — he said the rate of global temperature increase must be slowed.
Not exact matches
«Sea level observations are telling us that during the past 100 years sea level has risen at an average rate
of 1.7 millimeters per year,» most
of that due to thermal
expansion as the top 700 meters
of the
oceans warms and expands.
That is,
expansion of the
warm pool in the Indian
Ocean has far exceeded that in the Pacific
Ocean.
Sea levels have been rising worldwide over the past century by between 10 and 20 centimetres, as a result
of melting land - ice and the thermal
expansion of the
oceans due to a planetary
warming of around 0.5 degreeC.
According to calculations by other scientists, roughly half the rise comes from the thermal
expansion of the
oceans as they
warm.
«A fundamental question has been whether we can directly link
expansion of harmful algal blooms to a
warming ocean; this paper provides critical, quantitative evidence for just that trend, confirming an expected, but difficult to test, direct link between toxic blooms to climate,» said Dr. Raphael Kudela, Professor of Ocean Sciences, University of California Santa Cruz, a national toxic algae expert who was not part of the s
ocean; this paper provides critical, quantitative evidence for just that trend, confirming an expected, but difficult to test, direct link between toxic blooms to climate,» said Dr. Raphael Kudela, Professor
of Ocean Sciences, University of California Santa Cruz, a national toxic algae expert who was not part of the s
Ocean Sciences, University
of California Santa Cruz, a national toxic algae expert who was not part
of the study.
The world's
oceans have already risen by an average
of 8 inches over the last century from a combination
of water added by ice melt and the
expansion of ocean waters as they
warm.
Because existing phenomena — such as thermal
expansion of water from
warming — do not fully explain the corrected sea - level - rise number
of 3.3 millimeters, stored heat in the deep
ocean may be making a significant contribution, Cazenave said.
Global greenhouse gas emissions have already committed the residents
of the Maldives to a watery future:
ocean expansion due to
warming has raised sea levels enough to regularly deluge the islands, and melting glaciers will only make matters worse.
As the largest contributor is
ocean thermal
expansion,
warmer than expected temperatures would be a significant part
of the discrepancy.
[SLIDE 17] And so not surprisingly sea level is rising as a result not only
of the loss
of mountain glaciers and the great land ice sheets — losses from the great land ice sheets; but also thermal
expansion of sea water because the
ocean is getting
warmer.
The study was too limited to clarify whether the
warming Arctic climate and related summer
expansion of open water in the Arctic
Ocean is necessitating more long swims — or whether that is reducing the bear's survival rate or reproductive success.
Nick O, # 65: Will the rate
of sea level rise, due to
ocean warming and thermal
expansion, be somewhat faster than predicted in previous reports?
IF cool deep sea water were mixed relentlessly with surface water by some engineering method --(e.g. lots
of wave operated pumps and 800m pipes) could that enouromous cool reservoir
of water a) mitigate the thermal
expansion of the
oceans because
of the differential in thermal
expansion of cold and
warm water, and b) cool the atmosphere enough to reduce the other wise expected effects
of global
warming?
«The fact that we are seeing an
expansion of the
ocean's least productive areas as the subtropical gyres
warm is consistent with our understanding
of the impact
of global
warming,» he said.
Now scientists have measured a rapid recent
expansion of desert - like barrenness in the subtropical
oceans --- in places where surface waters have also been steadily
warming.
Anthropogenic forcing, resulting in thermal
expansion from
ocean warming and glacier mass loss, has very likely contributed to sea level rise during the latter half
of the 20th century.
And as a finishing touch there is
of course thermal
expansion of sea water — which leads to about one meter sea level rise for every one degree
of ocean warming — so that is two more.
We work with global
ocean circulation models to understand issues like the thermal
expansion of ocean waters due to global
warming or the effect
of changing
ocean currents on regional sea levels.
This is the basis for the first theoretical prediction for the effects
of global
warming mentioned in Section 1 — if global
warming causes the
oceans to heat up, this should (in theory) cause sea levels to rise, from «thermal
expansion».
Source: press release for Myers et al., 2015 Sea Levels 2 - 4 m Higher Until ~ 5,000 Years Ago Imply Surface Temps Were At Least 5 °C
Warmer According to the accepted (IPCC) formula for calculating the contribution
of ocean warming (thermal
expansion) to sea level rise upon reaching equilibrium, every additional degrees Celsius
of surface warmth yields -LSB-...]
The melting
of Greenland, Antarctica, mountain glaciers around the globe, and the corresponding
expansion of the volume
of the
ocean as it
warms, are expected to increase their pace.
Thermal
expansion — water swells as it heats — accounts for a substantial portion
of rising seas, so
warmer oceans mean even worse news for already threatened islands and coasts.
There are only so many possibilities: glaciers melting or thermal
expansion of the
oceans, both
of which imply
warmer temperatures; alternatively, the spontaneous creation
of water.
This is probably the most important indicator
of global
warming as it comes from only two occurrences - glacial melt and the
expansion of ocean water as it
warms.
Ever since the early 1990s, scientific reports have highlighted the vulnerability
of West Africa to inundation, flooding and loss
of key industries, food growing and infrastructure due to glacial melt, thermal
expansion of ocean waters set off by
warming, and an increase in storm strength in the North Atlantic.
Previous studies have considered mechanisms for the basin - scale
ocean warming, but not the causes of the observed IPWP expansion, where expansion in the Indian Ocean has far exceeded that in the Pacific O
ocean warming, but not the causes
of the observed IPWP
expansion, where
expansion in the Indian
Ocean has far exceeded that in the Pacific O
Ocean has far exceeded that in the Pacific
OceanOcean.
If some
of the
ocean heat uptake during the last 20 years has shifted from the shallow and
warm parts to the deeper and colder parts this would reduce the total thermal
expansion even if the total heat flux into the
oceans remained the same.
Since «there's an over two orders
of magnitude (~ 120) difference between the amount
of energy needed to add a litre to the
ocean from melting ice (~ 334KJ)[and] thermal
expansion of sea water (~ 40,000 KJ)», this means that sea - level rise, often offered as a «proxy» for «global
warming», is actually not important.
«The distribution, frequency and intensity
of these events have increased across the globe and this study links this
expansion to
ocean warming in some regions
of the North Atlantic and North Pacific
oceans.»
If there is deep - water formation in the final steady state as in the present day, the
ocean will eventually
warm up fairly uniformly by the amount
of the global average surface temperature change (Stouffer and Manabe, 2003), which would result in about 0.5 m
of thermal
expansion per degree celsius
of warming, calculated from observed climatology; the EMICs in Figure 10.34 indicate 0.2 to 0.6 m °C — 1 for their final steady state (year 3000) relative to 2000.
ocean is
of the order
of 1000 years, thermal
expansion is expected to be relatively slow and predictable, although shifts in
ocean circulation can influence the details
of the
warming and sea - level rise.
This
expansion of OMZs is due to nutrient runoff makes the
ocean more vulnerable to decreasing solubility
of O2 in a
warmer ocean.
As explained in the press release, the scientists began with the measure
of sea level rise between 2005 and 2013, then deducted the amount
of rise due to meltwater (e.g., melting ice sheets and loss
of glacier mass worldwide) and then the amount
of rise due to the
expansion of water from the
warming in the upper portion
of the world's
oceans (which scientists have good data on).
Sea level is rising, primarily in response to a
warming planet, through thermal
expansion of the
oceans, and also via the loss
of land ice as
ocean and air temperatures increase, melting ice and speeding the flow
of non-floating ice to form floating icebergs.
At the same time, the
ocean is expected to
warm with an associated
expansion of the oxygen minimum layer (OML).
With a 2 °C
warming, the solubility would decrease by 14 μM resulting in a large
expansion of areas depleted
of dissolved oxygen and turning large areas
of the
ocean into places where aerobic life disappears.
So you need to look at a wide range
of indicators all
of which have independent sources
of error (for instance, errors in satellites are not likely to be correlated with errors in weather stations or
ocean buoys) and see if your understanding matches all
of the different aspects that you expect from the theory (stratospheric cooling,
ocean warming, Arctic melt, poleward and upward
expansion of biomes etc...).
We were talking about thermal
expansion / sea level rise
of the
ocean from a
warming ocean, not sea level rise from adding more water.
The principal causes are clear: global decline
of land ice (mountain glaciers & ice sheets) and thermal
expansion of ocean water (water expands as it becomes
warmer).
Could it have been that much more heat was propotionately gained by the upper
warmer layers
of the
oceans (where the thermal
expansion coefficient is much higher)?
It can't except by heating the surface, leading to increased convection, leading to a
warming of the atmosphere, leading to an
expansion of the atmosphere, similar to the
expansion of the
oceans.
Ocean Warming 50 % Greater Than IPCC Report At the Copenhagen Climate Congress back in March, the synthesis report produced says that current estimates show that ocean warming is 50 % greater than had been reported in the 2007 IPCC report and that sea level rise reported in previous decades had largely been the result of thermal expan
Ocean Warming 50 % Greater Than IPCC Report At the Copenhagen Climate Congress back in March, the synthesis report produced says that current estimates show that ocean warming is 50 % greater than had been reported in the 2007 IPCC report and that sea level rise reported in previous decades had largely been the result of thermal exp
Warming 50 % Greater Than IPCC Report At the Copenhagen Climate Congress back in March, the synthesis report produced says that current estimates show that
ocean warming is 50 % greater than had been reported in the 2007 IPCC report and that sea level rise reported in previous decades had largely been the result of thermal expan
ocean warming is 50 % greater than had been reported in the 2007 IPCC report and that sea level rise reported in previous decades had largely been the result of thermal exp
warming is 50 % greater than had been reported in the 2007 IPCC report and that sea level rise reported in previous decades had largely been the result
of thermal
expansion.
(NB,
warming of the
oceans also causes sea level rise through thermal
expansion
Sea - level rise caused by thermal
expansion (in the range
of 10 to 30 cm per century) is likely to continue for centuries (even if the
warming asymptotes to values close to CEW G by 2100) because
of the time required for mixing
of the heating to deeper
oceans.
(By the way, neither has sea - level rise due to thermal
expansion, because the thermal
expansion coefficient is several times larger for
warm surface waters than for the cold deep waters — again it is
warming in the surface layers that counts, while the total
ocean heat content tells us little about the amount
of sea - level rise.)