Instruct: Given a question, retrieve relevant passages that answer the question.
Query: Is another ice age predicted for the future?
The idea that ice ages cycles were predictable appears to have become conflated with the idea that another one was due "soon" - perhaps because much of this study was done by geologists, who are accustomed to dealing with very long time scales and use "soon" to refer to periods of thousands of years. A strict application of the Milankovitch theory does not allow the prediction of a "rapid" ice age onset (i.e., less than a century or two) since the fastest orbital period is about 20,000 years. Some creative ways around this were found, notably one championed by Nigel Calder under the name of "snowblitz", but these ideas did not gain wide acceptance.
Reef scientist Terry Done has predicted that a one-degree rise in global temperature would result in 82% of the reef bleached—two degrees would result in 97%, while three degrees would result in "total devastation". A predictive model based on the 1998 and 2002 bleaching events has concurred that a temperature rise of three degrees would result in total coral mortality.
Between the 14th century and 1850, many of the glaciers on Mount Rainier advanced to their farthest extent downvalley since the last ice age. Many advances of this sort occurred worldwide during this time period known to geologists as the Little Ice Age. During the Little Ice Age, the Nisqually Glacier advanced to a position downvalley from the site of the Glacier Bridge, Tahoma and South Tahoma Glaciers merged at the base of Glacier Island, and the terminus of Emmons Glacier reached within of the White River Campground.
The EAIS holds enough ice to raise global sea levels by 53.3 m and is considerably larger in area and mass than the West Antarctic Ice Sheet (WAIS). It is separated from the WAIS by the Transantarctic Mountains. The EAIS is the driest, windiest, and coldest place on Earth, with temperatures reported down to nearly -100°C. The EAIS holds the thickest ice on Earth, at 15,700 ft (4,800 m). It is home to the geographic South Pole and the Amundsen-Scott South Pole Station.
Some of Antarctica has been warming up; particularly strong warming has been noted on the Antarctic Peninsula. A study by Eric Steig published in 2009 noted for the first time that the continent-wide average surface temperature trend of Antarctica is slightly positive at >0.05 °C (0.09 °F) per decade from 1957 to 2006. This study also noted that West Antarctica has warmed by more than 0.1 °C (0.2 °F) per decade in the last 50 years, and this warming is strongest in winter and spring. This is partly offset by autumn cooling in East Antarctica. There is evidence from one study that Antarctica is warming as a result of human carbon dioxide emissions, but this remains ambiguous. The amount of surface warming in West Antarctica, while large, has not led to appreciable melting at the surface, and is not directly affecting the West Antarctic Ice Sheet's contribution to sea level. Instead the recent increases in glacier outflow are believed to be due to an inflow of warm water from the deep ocean, just off the continental shelf. The net contribution to sea level from the Antarctic Peninsula is more likely to be a direct result of the much greater atmospheric warming there.
Ice cap climate is the world's coldest climate, and includes the coldest places on Earth. With an average temperature of , Vostok, Antarctica is the coldest place in the world, and has also recorded the lowest temperature, . The following chart indicates the average and record temperatures in this research station through a year:
A September 2008 study of zircons found that Australian Hadean rock holds minerals pointing to the existence of plate tectonics as early as 4 billion years.
If this is true, the time when Earth finished its transition from having a hot, molten surface and atmosphere full of carbon dioxide, to being very much like it is today, can be roughly dated to about 4.0 billion years ago. The actions of plate tectonics and the oceans trapped vast amounts of carbon dioxide, thereby reducing the greenhouse effect and leading to a much cooler surface temperature and the formation of solid rock, and possibly even life.
A 1996 article in "The New York Times" included the comments of several other experts. Jerry D. Mahlman, director of the Geophysical Fluid Dynamics Laboratory, did not accept Lindzen's assessment of the science, and said that Lindzen had "sacrificed his luminosity by taking a stand that most of us feel is scientifically unsound." Mahlman did, however, admit that Lindzen was a "formidable opponent". William Gray of Colorado State University basically agreed with Lindzen, describing him as "courageous". He said, "A lot of my older colleagues are very skeptical on the global warming thing". He added that while he regarded some of Lindzen's views as flawed, he said that, "across the board he's generally very good". John Wallace of the University of Washington agreed with Lindzen that progress in climate change science had been exaggerated, but said there are "relatively few scientists who are as skeptical of the whole thing as Dick [Lindzen] is".
In a letter to "Nature", Veizer et al.(2000), compared the reconstruction of tropical sea surface temperatures throughout the Phanerozoic eon (the past ~550 Myr) with the variable galactic cosmic rays and concluded that their results can be reconciled if atmospheric carbon dioxide concentrations were not the principal driver of climate variability on geological timescales for at least one-third of the Phanerozoic eon, or if the reconstructed carbon dioxide concentrations are not reliable.
According to the GBRMPA in 2014, the most significant threat to the status of the Great Barrier Reef is climate change, due to the consequential rise of sea temperatures, gradual ocean acidification and an increase in the number of "intense weather events". Hughes writes of "the demonstrable failure of the state and Commonwealth" to address the issue of climate change in his August 2014 article. Furthermore, a temperature rise of between two and three degrees Celsius would result in 97% of the Great Barrier Reef being bleached every year.
Vostok Station has an ice cap climate ("EF"), with subzero temperatures year round, typical as with much of Antarctica. Annual precipitation is only (all occurring as snow), making it one of the driest places on Earth. On average, Vostok station receives 26 days of snow per year. Average summer temperature is and average winter temperature is . It is one of the coldest spots on earth, with the lowest recorded temperature being .
Antarctica, on average, is the coldest, driest, and windiest continent, and has the highest average elevation of all the continents. Most of Antarctica is a polar desert, with annual precipitation of only 200 mm (8 in) along the coast and far less inland. The temperature in Antarctica has reached −89.2 °C (−128.6 °F) (or even −94.7 °C (−135.8 °F) as measured from space), though the average for the third quarter (the coldest part of the year) is −63 °C (−81 °F). Anywhere from 1,000 to 5,000 people reside throughout the year at research stations scattered across the continent. Organisms native to Antarctica include many types of algae, bacteria, fungi, plants, protista, and certain animals, such as mites, nematodes, penguins, seals and tardigrades. Vegetation, where it occurs, is tundra.
On May 19, 2011, NOAA released their first forecast for the 2011 Atlantic hurricane season. The organization expected 12–18 named storms, 6–10 hurricanes, and 3–6 major hurricanes would form in the Atlantic during 2011, citing above-normal sea surface temperatures, a weakening La Niña, and the effect of the warm regime of the Atlantic multidecadal oscillation. NOAA also stated that, when looking at climate models, "activity comparable to some of the active seasons since 1995" could occur. On May 26, the UK Met Office (UKMO) issued a forecast of a slightly above-average season. They predicted 13 tropical storms with a 70% chance that the number would fall between 10 and 17. However, they did not – and do not – issue forecasts on the number of hurricanes and major hurricanes. The team also predicted an ACE Index of 151 with a 70% chance that the index would be in the range 89 to 212.
Of official weather stations which are currently in operation, Vostok is the coldest on earth in terms of mean annual temperature. However, it has been disputed that Vostok Station is the coldest known location on earth. The now inactive Plateau Station, located on the central Antarctic plateau, is believed to have recorded an average yearly temperature that was consistently lower than that of Vostok Station during the 37-month period that it was active in the late 1960s, and satellite readings have routinely detected colder temperatures in areas between Dome A and Dome F.
Vostok is one of the coldest places on Earth. The average temperature of the cold season (from April to October) is about , while the average temperature of the warm season (from November to March) is about .
In July 2017 UNESCO published in a draft decision, expressing serious concern about the impact of coral bleaching on the Great Barrier Reef. The draft decision also warned Australia that it will not meet the targets of the Reef 2050 report without considerable work to improve water quality.
Global sea level change for much of the last century has generally been estimated using tide gauge measurements collated over long periods of time to give a long-term average. More recently, altimeter measurements—in combination with accurately determined satellite orbits—have provided an improved measurement of global sea level change. To measure sea levels prior to instrumental measurements, scientists have dated coral reefs that grow near the surface of the ocean, coastal sediments, marine terraces, ooids in limestones, and nearshore archaeological remains. The predominant dating methods used are uranium series and radiocarbon, with cosmogenic radionuclides being sometimes used to date terraces that have experienced relative sea level fall. In the early Pliocene, global temperatures were 1–2˚C warmer than the present temperature, yet sea level was 15–25 meters higher than today.
Russia is planning to start building new icebreakers, Project 22220 after 2010.
In June 2008 the head of the state nuclear corporation Rosatom, Sergei Kiriyenko, said "It is important to not only use the existing fleet of icebreakers, but also to build new ships, and the first nuclear icebreaker of a new generation will be built by 2015. This should be an icebreaker capable of moving in rivers and seas", he said. He went on saying that the Iceberg Design Bureau in St. Petersburg would prepare the design of the icebreaker by 2009. According to the BBC the LK-60 (ЛК60Я) will be the biggest nuclear-powered icebreaker that was ever built. Vladimir Putin said in 2010, Russia builds at least three nuclear icebreakers of the new generation in the period from 2012 to 2020. Sergei Kiriyenko, head of the state nuclear corporation Rosatom ordered the responsible operator Atomflot to build up to three nuclear icebreakers until 2016. The construction of a nuclear-powered icebreaker takes eight years, the fuel endurance is about 25 years and the reactor can be refueled. According to the Transport Ministry, Russia needs six new icebreakers in the future.
Winter weather conditions in Toronto can vary greatly from one year to another and is significantly affected by global weather patterns such as El Nino Southern Oscillation (ENSO). El Nino winters are generally mild and dry, with decreased snowfall (such as the winters of 2009-2010 and 2015-2016), while La Nina winters tend have more precipitation (the aforementioned winters of 1999 and 2008 are both La-Nina). ENSO Neutral years are more unpredictable.
According to a Reuters report, the [[Himalayas|Himalayan]] glaciers that are the sources of Asia's biggest rivers—[[Ganges]], [[Indus]], [[Brahmaputra]], [[Yangtze]], [[Mekong]], [[Salween]] and [[Yellow River|Yellow]]—could diminish as temperatures rise. Approximately 2.4 billion people live in the [[drainage basin]] of the Himalayan rivers. India, China, [[Pakistan]], [[Bangladesh]], [[Nepal]] and [[Myanmar]] could experience floods followed by [[drought]]s in coming decades. The Indus, Ganges and Brahmaputra river basins support 700 million people in Asia. In India alone, the Ganges provides water for drinking and farming for more than 500 million people. It has to be acknowledged, however, that increased seasonal runoff of Himalayan glaciers led to increased agricultural production in northern India throughout the 20th century. Research studies suggest that climate change will have a marked affect on meltwater in the Indus Basin.
The mission will seek signs of habitable conditions on Mars in the ancient past, and will also search for evidence —or biosignatures— of past microbial life. The rover is planned for launch in 2020 on an Atlas V-541, and the Jet Propulsion Laboratory will manage the mission. The mission is part of NASA's Mars Exploration Program.
Croll's theory predicted multiple ice ages, asynchronous in northern and southern hemispheres, and that the last ice ages should have ended about 80,000 years ago. Evidence was just then emerging of multiple ice ages, and geologists were interested in a theory to explain this. Geologists were not then able to date sediments accurately enough to determine if glaciation was synchronous between the hemispheres, though the limited evidence more pointed towards synchronicity than not. More crucially, estimates of the recession rate of the Niagara Falls indicated that the last ice age ended 6,000 to 35,000 years ago – a large range, but enough to rule out Croll's theory, to those who accepted the measurements.
The Arctic ocean will likely be free of summer sea ice before the year 2100, but many different dates have been projected. One study suggests 2060–2080 and another suggests 2030. A 2013 study showed that simply extending summertime ice melting trends into the future in a straight line predicts an ice-free summertime Arctic as early as by 2020.
Historically, there have been cyclical ice ages in which glacial sheets periodically covered the higher latitudes of the continents. Ice ages may occur because of changes in ocean circulation and continentality induced by plate tectonics. The Milankovitch theory predicts that glacial periods occur during ice ages because of astronomical factors in combination with climate feedback mechanisms. The primary astronomical drivers are a higher than normal orbital eccentricity, a low axial tilt (or obliquity), and the alignment of summer solstice with the aphelion. Each of these effects occur cyclically. For example, the eccentricity changes over time cycles of about 100,000 and 400,000 years, with the value ranging from less than 0.01 up to 0.05. This is equivalent to a change of the semiminor axis of the planet's orbit from 99.95% of the semimajor axis to 99.88%, respectively.
Many scientists have attempted to estimate when the Arctic will be "ice-free". Professor Peter Wadhams of the University of Cambridge is among these scientists. Wadhams and several others have noted that climate model predictions have been overly conservative regarding sea ice decline. A 2013 paper suggested that models commonly underestimate the solar radiation absorption characteristics of wildfire soot. A 2006 paper predicted "near ice-free September conditions by 2040". Overland and Wang (2013) investigated three different ways of predicting future sea ice levels. From sea ice models and recent satellite images it can be expected that a sea ice free summer will come before 2020. The IPCC AR5 (for at least one scenario) estimates an ice-free summer might occur around 2050. The Third U.S. National Climate Assessment (NCA), released May 6, 2014, reports that the Arctic Ocean is expected to be ice free in summer before mid-century. Models that best match historical trends project a nearly ice-free Arctic in the summer by the 2030s. However, these models do tend to underestimate the rate of sea ice loss since 2007. Based on the outcomes of several different models, Overland and Wang (2013) put the early limit for a sea ice free summer Arctic near 2040.