Over the long - term, melting of the West Antarctic Ice Sheet could yield as much as 10 to 14 feet
of global average sea level rise, with local sea level rise varying considerably depending on land elevation trends, ocean currents and other factors.
It is very likely that the mean rate
of global averaged sea level rise was 1.7 [1.5 to 1.9] mm yr — 1 between 1901 and 2010, 2.0 [1.7 to 2.3] mm yr — 1 between 1971 and 2010 and 3.2 [2.8 to 3.6] mm yr — 1 between 1993 and 2010.
Not exact matches
With rates
of sea -
level rise along parts
of the nation's Eastern seaboard increasing three to four times faster than the
global average, experts are working to mitigate the effects by identifying threats, organizing collaboration among governments and organizations, as well as examining better...
With rates
of sea -
level rise along parts
of the nation's Eastern seaboard increasing three to four times faster than the
global average, experts are working to mitigate the effects by identifying threats, organizing collaboration among governments and organizations, as well as examining better communication techniques.
The report's authors, who also include scientists from federal agencies, Columbia University and the South Florida Water Management District, concluded that evidence supports a «worst - case»
global average sea -
level rise of about 8.2 feet by 2100.
Global average sea level has
risen by roughly 0.11 inch (3 millimeters) per year since 1993 due to a combination
of water expanding as it warms and melting ice sheets.
The report finds that the U.S. is particularly vulnerable to projected
sea level rise; areas such as the Northeast and western Gulf
of Mexico could face rates that exceed
global average sea level rise.
The reduction in the ice mass has contributed to
global average sea -
level rise of 25 millimeters.
A «business - as - usual» climate scenario (RCP8.5) will lead to another 74 centimeters
of global average sea -
level rise by 2100.
Indeed, the most recent IPCC report concluded that the
sea -
level rise contribution associated such an event «can not be precisely quantified,» but would contribute «several tenths
of a meter»
of global average sea -
level rise by 2100.
Third, using a «semi-empirical» statistical model calibrated to the relationship between temperature and
global sea -
level change over the last 2000 years, we find that, in alternative histories in which the 20th century did not exceed the
average temperature over 500-1800 CE,
global sea -
level rise in the 20th century would (with > 95 % probability) have been less than 51 %
of its observed value.
Rob and Dave's research found that these processes give
rise to the potential for more than one meter
of global average sea -
level rise from Antarctica alone over the course
of this century, and more than 15 meters over the next five centuries.
For a future
of continued growth in emissions the new results indicate a likely
global average sea -
level rise between 1.1 and 2.1 meters (3.6 to 6.9 feet)-- roughly double the IPCC - consistent estimate.
One recent modeling study focused on this mode
of instability estimated that the Antarctic ice sheet has a 1 - in - 20 chance
of contributing about 30 centimeters (1.0 feet) to
global average sea -
level rise over the course
of this century and 72 centimeters (2.4 feet) by the end
of the next century.
Regardless
of emissions pathway and approach, there is likely to be between about 16 and 40 cm (0.5 and 1.3 feet)
of global average sea -
level rise in the first half
of the century.
The Fourth Assessment Report finds that «Warming
of the climate system is unequivocal, as is now evident from observations
of increases in
global average air and ocean temperatures, widespread melting
of snow and ice, and
rising mean
sea level.
Take South Florida, where, a few years back, the rate
of sea level rise shot up from close to the
global average to something much higher.
Ocean heating accounts for about 40 percent
of global sea level rise, because water expands as it warms up;
global average sea level from January through November was also a record high, the WMO said.
Imagine
sea levels rising by feet instead
of inches,
global average temperatures increasing by many degrees instead
of just fractions and an increase in other cataclysmic, costly and fatal weather events.
3 Millimeters explores the Eastern Shore
of Maryland, where the
sea level is
rising at twice the
global average - a process without emergency brakes.
«These new results indicate that relative
sea levels in New Zealand have been
rising at an
average rate
of 1.6 mm / yr over the last 100 years — a figure that is not only within the error bounds
of the original determination, but when corrected for glacial - isostatic effects has a high
level of coherency with other regional and
global sea level rise determinations.
But the
global average rise in
sea level is a chimera
of many factors acting differently at various locations.
«suggesting that Arctic warming will continue to greatly exceed the
global average over the coming century, with concomitant reductions in terrestrial ice masses and, consequently, an increasing rate
of sea level rise.»
The increase in these winds has caused eastern tropical Pacific cooling, amplified the Californian drought, accelerated
sea level rise three times faster than the
global average in the Western Pacific and has slowed the
rise of global average surface temperatures since 2001.
You have «What is the likelihood that
global average sea level will
rise more during this century than the current worst - case scenario
of the Intergovernmental Panel on Climate Change?»
Warming
of the climate system is unequivocal, as is now evident from observations
of increases in
global average air and ocean temperatures, widespread melting
of snow and ice, and
rising global average sea level.
Having said that, it is a really small effect — if the entire Arctic summer
sea ice pack melted (
average thickness 2 metres, density ~ 920 kg / m3, area 3 × 10 ^ 6 km ^ 2 (0.8 % total ocean area) = > a 4.5 cm
rise instantly which implies a
global sea level rise of 0.36 mm.
For example, if this contribution were to grow linearly with
global average temperature change, the upper ranges
of sea level rise for SRES scenarios shown in Table SPM - 3 would increase by 0.1 m to 0.2 m. Larger values can not be excluded, but understanding
of these effects is too limited to assess their likelihood or provide a best estimate or an upper bound for
sea level rise.
For example, the latest (fifth) assessment report from the U.N.'s Intergovernmental Panel on Climate Change (IPCC) projects that the
global average sea level rise over the course
of the 21st century would be in the range
of 10 to 32 inches, with a mean value
of about 19 inches.
The most severe impacts
of climate change — damaging and often deadly drought,
sea -
level rise, and extreme weather — can only be avoided by keeping
average global temperatures within 2 degrees C (3.6 degrees F)
of pre-industrial
levels.
That would likely mean that also the official UN climate goal
of limiting the
average world temperature
rise to no more than 2 degrees Celsius — a target linked to 450 ppm CO2 equivalent stabilisation scenarios (practically ambitious, theoretically weak)-- will eventually lead to many meters
of global sea level rise.
It found eight
of the atolls and almost three - quarters
of the islands grew during the study period, lifting Tuvalu's total land area by 2.9 percent, even though
sea levels in the country
rose at twice the
global average.
Each base's exposure is calculated based on the National Climate Assessment's midrange or «intermediate - high»
sea level rise scenario (referred to in this analysis as «intermediate»), which projects a
global average increase
of 3.7 feet above 2012
levels, by 2100; and a «highest» scenario based on a more rapid rate
of increase, which projects a
global average increase
of 6.3 feet.
Climate scientists have been able to close the
sea level «budget» by accounting for the various factors that are causing
average global sea levels to
rise at the measured rate
of about 3.2 millimeters per year since 1992 (when altimeters were launched into space to truly measure
global sea level).
The
global average sea level has already
risen by about eight inches since 1901, with up to another two and a half feet
of sea level rise possible by 2100, according to the most recent projections from the U.N. Intergovernmental Panel on Climate Change.
Global average sea level is projected to
rise by 18 to 59 cm by the end
of the 21st century (2090 - 2099), depending on the scenario (Table 3).
In her role, she ensures that all program analyses reflect robust and relevant climate science, and researches the influence
of major carbon producers on
rising global average temperatures and
sea level.
Under the IPCC Business As Usual emissions scenario, an
average rate
of global mean
sea level rise of about 6 cm per decade over the next century (with an uncertainty range
of 3 — 10 cm per decade).
Fourth Assessment Report (2007):
Global average sea level rose at an
average rate
of 1.8 [1.3 to 2.3] mm per year over 1961 to 2003.
If we do nothing to reduce our carbon emissions, scientists project that
global sea level could
rise as much as nearly two feet (59 centimeters) over recent
average levels by the end
of this century.14, 15 If, on the other hand, we make significant efforts to reduce heat - trapping emissions,
sea -
level rise between now and the end
of the century could be limited to at most 1.25 feet (38 centimeters).14, 15
Global average sea level rose at an
average rate
of 1.8 [1.3 to 2.3] mm per year over 1961 to 2003.
The
global average rate
of sea level rise measured by TOPEX / Poseidon satellite altimetry during 1993 to 2003 is 3.1 ± 0.7 mm yr — 1.
► Eustatic
sea -
level rise is a change in
global average sea level brought about by an increase in the volume
of the world ocean.
For instance, it found that for the year 2040 on the worst - case emissions pathway, the
global average sea -
level rise would be 0.2 meters (0.65 feet), but «more than 90 percent
of coastal areas will experience
sea level rise exceeding the
global estimate.»
ocean temperatures, widespread melting
of snow and ice, and
rising global average sea level,» are three disjoint sources
of confirmation that give us reliable enough trend information to establish consilience about what we may say after 2005 on HadCRUT4.
From this it can be seen that in some places
sea level trend is
rising whilst in others it is falling, so giving a
global average disguises the nuances
of what is happening locally, where it matters.
Boutrous pointed out that while
global sea levels are
rising on
average, some evidence shows that
sea levels have fallen in specific regions, and coastal flooding in places like the San Francisco Bay Area is also a function
of local conditions like land subsidence.
The Fourth Assessment Report finds that «Warming
of the climate system is unequivocal, as is now evident from observations
of increases in
global average air and ocean temperatures, widespread melting
of snow and ice, and
rising mean
sea level.
Their 0.2 mm / yr figure is taken to be consistent with an observed total
sea level rise of 1.6 mm / yr from JASON - 1 and 2, but
global averages from those satellites indicate a
rise of about 2.5 mm / yr over the same period.
They conclude that while the rate
of increase
of average global surface temperatures has slowed since 1998, melting
of Arctic ice,
rising sea levels, and warming oceans have continued apace.