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Current sea level rise

Trends in global average absolute sea level, 1870–2008.[1] Changes in sea level since the end of the last glacial episode. Current sea level rise is about 3 mm/year worldwide. According to the US National Oceanic and Atmospheric Administration (NOAA), "this is a significantly larger rate than the sea-level rise averaged over the last several thousand years", and the rate may be increasing.[2] This rise in sea levels around the world potentially affects human populations in coastal and island regions[3] and natural environments like marine ecosystems.[4] Between 1870 and 2004, global average sea levels rose 195 mm (7.7 in), 1.46 mm (0.057 in) per year.[5] From 1950 to 2009, measurements show an average annual rise in sea level of 1.7 ± 0.3 mm per year, with satellite data showing a rise of 3.3 ± 0.4 mm per year from 1993 to 2009,[6] a faster rate of increase than previously estimated.[7] It is unclear whether the increased rate reflects an increase in the underlying long-term trend.[8]

Related:  Physical evidence

Evidence The Earth's climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era — and of human civilization. Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives. Scientific evidence for warming of the climate system is unequivocal. The current warming trend is of particular significance because most of it is very likely human-induced and proceeding at a rate that is unprecedented in the past 1,300 years.1

Shutdown of thermohaline circulation A summary of the path of the thermohaline circulation. Blue paths represent deep-water currents, while red paths represent surface currents A shutdown or slowdown of the thermohaline circulation is a postulated effect of global warming. Thermohaline circulation and fresh water[edit] The red end of the spectrum indicates slowing in this presentation of the trend of velocities derived from NASA Pathfinder altimeter data from May 1992 to June 2002. Source: NASA. Ocean acidification NOAA provides evidence for upwelling of corrosive "acidified" water onto the Continental Shelf. In the figure above, note the vertical sections of (A) temperature, (B) aragonite saturation, (C) pH, (D) DIC, and (E) pCO2 on transect line 5 off Pt. St. George, California. The potential density surfaces are superimposed on the temperature section.

Climate Change, Deforestation, Biomes and Ocean Currents, Plankton, Endangered Species - Earth Web Site Click for more detail Thermohaline Change Evidence is growing that the thermohaline current may be slowed or stopped by cold fresh water inputs to the Arctic and North Atlantic oceans. This could occur if global warming is sufficient to cause large scale melting of arctic sea ice and the Greenland ice sheet. Such a change in the current may be gradual (over centuries) or very rapid (over a few years). Either would cause planet wide changes in climate. This effect may be part of what starts and stops the ice ages.

Global Warming Mapped The world is getting warmer. Whether the cause is human activity or natural variability, thermometer readings all around the world have risen steadily since the beginning of the Industrial Revolution. According to an ongoing temperature analysis conducted by scientists at NASA’s Goddard Institute for Space Studies (GISS), the average global temperature on Earth has increased by about 0.8°Celsius (1.4°Fahrenheit) since 1880. The scientific consensus on global warming « Later On From the American Association for the Advancement of Science (AAAS), the preeminent scientific organization in the US. Note that this article is not based on a mere count of articles, but rather looks at statements from various scientific organizations. Science 3 December 2004: Vol. 306. no. 5702, p. 1686 DOI: 10.1126/science.1103618BEYOND THE IVORY TOWER: The Scientific Consensus on Climate ChangeNaomi Oreskes*Policy-makers and the media, particularly in the United States, frequently assert that climate science is highly uncertain. Some have used this as an argument against adopting strong measures to reduce greenhouse gas emissions.

Temperature record of the past 1000 years For information on the description of the Medieval Warm Period and Little Ice Age in various IPCC reports see MWP and LIA in IPCC reports The temperature record of the past 2000 years from several different proxy methods. Individual proxy records, such as tree ring widths and densities used in dendroclimatology, are calibrated against the instrumental record for the period of overlap. Arctic Warming is Altering Weather Patterns, Study Shows EDITOR'S NOTE: This story was originally published April 3. Given recent news that Arctic sea ice set a record low, it's a reminder that changes in the Arctic can affect the U.S. and Europe. By showing that Arctic climate change is no longer just a problem for the polar bear, a new study may finally dispel the view that what happens in the Arctic, stays in the Arctic.

AMS confirms Climate Change and Man's Role Weathercasters in the U.S. not only tend to not ever mention climate change, but the majority of them do not even believe it is human-caused, as an article I recently wrote shows. However, that may change. The American Meteorological Society (AMS) released an official position statement on climate change this week which not only said that it is occurring, but it is human-caused. What is so great about the statement by the AMS is that it includes so much information about climate change, including that there is scientific consensus. The AMS makes it clear that the statement is "based on the peer-reviewed scientific literature and is consistent with the vast weight of current scientific understanding."