Sentences with phrase «past ice ages on»

Not exact matches

Explore the Ice Age with hands - on glacier demonstrations and activities, as well as real geologic clues to New England's icy past (Cambridge)

On land, the capacity of animals to carry nutrients away from concentrated «hotspots,» the team writes, has plummeted to eight percent of what it was in the past — before the extinction of some 150 species of mammal «megafauna» at the end of the last ice age.

As Weir points out, it likely owes its survival as a species on being geographically isolated from its parental species at some point during a past ice age when rainforest coverage contracted, and wide rivers formed natural barriers.

The Past and Future Ocean Circulation from a Contemporary Perspective, in AGU Monograph, 173, A. Schmittner, J. Chiang and S. Hemming, Eds., 53 - 74, (pdf)» Wunsch's publications page is great food - for - thought, I particularly enjoyed his papers on Ice Age changes and the Milankovitch cycles.

Moreover, random interactions within the sun's magnetic field can flip the fluctuations from one cycle length to the other, matching the paleo - temperature record for ice ages on Earth for over the past 5.3 million years, when ice ages occurred occurred roughly every 41,000 years until about a million years ago when they switched to a roughly 100,000 - year cycle.

During the ice age, a woolly mammoth loner with a tragic past joins a wisecracking sloth and a scheming saber toothed tiger on a dangerous journey to reunite a one year old boy with his hunter father.

Like other sea - holes or «vertical caves,» the Great Blue Hole in Belize's Lighthouse Reef actually formed on dry land, during a past ice age when the sea level was a lot lower than it is today.

There are echoes of this past however, and it was interesting when we included the George Bellows painting of ice floes in the Hudson River on the top floor, because that piece harkens a little bit to aspects of late 19th - century art and the age of American Impressionism, with artists like Childe Hassam and William Merritt Chase.

Having read the comments here and in Jones and Mann (2004) «Climate over past millennia», I have been reflecting on some of the comments about the hockey stick wrt the Medieval Warm Period (MWP) and the Little Ice Age (LIA).

(Much of the glaciological literature on termination of large ice ages requires ice - sheet growth past a threshold size.)

There are many who will not like this recent paper published in Nature Communications on principle as it talks of the hiatus in global temperatures for the past 20 years or so, that the Little Ice Age was global in extent, and that climate models can not account for the observations we already have let alone make adequate predictions about what will happen in the future.

There is still some discussion about how exactly this starts and ends ice ages, but many studies suggest that the amount of summer sunshine on northern continents is crucial: if it drops below a critical value, snow from the past winter does not melt away in summer and an ice sheet starts to grow as more and more snow accumulates.

Climate model simulations confirm that an Ice Age can indeed be started in this way, while simple conceptual models have been used to successfully «hindcast» the onset of past glaciations based on the orbital changes.

An editorial in The Time magazine on June 24, 1974, quoted concerned scientists as voicing alarm over the atmosphere «growing gradually cooler for the past three decades», «the unexpected persistence and thickness of pack ice in the waters around Iceland,» and other harbingers of an ice age that could prove «catastrophic.»

Rohling et al. (2013) provide a good overview on what we know about rates of sea level rise in the Holocene, past ice ages and interglacials:

«The authors write that «the Mediterranean region is one of the world's most vulnerable areas with respect to global warming,»... they thus consider it to be extremely important to determine what impact further temperature increases might have on the storminess of the region... produced a high - resolution record of paleostorm events along the French Mediterranean coast over the past 7000 years... from the sediment bed of Pierre Blanche Lagoon [near Montpellier, France]... nine French scientists, as they describe it, «recorded seven periods of increased storm activity at 6300 - 6100, 5650 - 5400, 4400 - 4050, 3650 - 3200, 2800 - 2600, 1950 - 1400, and 400 - 50 cal yr BP,» the latter of which intervals they associate with the Little Ice Age.

Well; if a statement regarding atmospheric cooling is taking place, and we know from past experience (climate history) that if this cooling continues and the build up of ice continues in Antartica like it is; then it is possible that the planet may very well be headed back into an ice age - and when this «atmospheric cooling» trend is mentioned on the GISS [NASA] Webpage, and by one of the GISS scientists (Kate Marvel, a climatologist at GISS and the paper's lead author) then i would have to conclude that the are embracing the science revealing evidence that such mechanics are, taking place, and I view their statemnt as an endorsement and ot their recognition, of global cooling.

According to the report, which follows a series of comprehensive reports from the IPCC in the past year on climate science and impacts, temperatures already have increased by 0.85 degrees Celsius since 1880, a more rapid shift in the climate than that which heralded the end of the last ice age about 10,000 years ago.

Studies in the past have also confirmed the value of this feedback on the AIS evolution during the ice age.

As I have stated publicly on many occasions, there is no definitive scientific proof, through real - world observation, that carbon dioxide is responsible for any of the slight warming of the global climate that has occurred during the past 300 years, since the peak of the Little Ice Age.

As massive ice sheets retreated during past ice ages, their weight on the land below lifted and the land rebounded.

Proxies such as these provide most knowledge of past climate fluctuations, such as the Medieval Warm Period from about 800 to 1300 and the Little Ice Age, centred on the year 1700.

But what caught my eye was a really interesting companion article, highlighting research on Roman seaside ruins which indicate that for the past two millennia or so that sea levels have been comparatively steady, and that the level of increase we witness today really started with industrialization.Though there's no doubt that sea levels around the globe have fluctuated widely, as in hundreds of foot differences — at the end of last ice age when ice sheets melted sea level rose almost 400 feet.

The models heavily relied upon by the Intergovernmental Panel on Climate Change (IPCC) had not projected this multidecadal stasis in «global warming»; nor (until trained ex post facto) the fall in TS from 1940 - 1975; nor 50 years» cooling in Antarctica (Doran et al., 2002) and the Arctic (Soon, 2005); nor the absence of ocean warming since 2003 (Lyman et al., 2006; Gouretski & Koltermann, 2007); nor the onset, duration, or intensity of the Madden - Julian intraseasonal oscillation, the Quasi-Biennial Oscillation in the tropical stratosphere, El Nino / La Nina oscillations, the Atlantic Multidecadal Oscillation, or the Pacific Decadal Oscillation that has recently transited from its warming to its cooling phase (oceanic oscillations which, on their own, may account for all of the observed warmings and coolings over the past half - century: Tsoniset al., 2007); nor the magnitude nor duration of multi-century events such as the Mediaeval Warm Period or the Little Ice Age; nor the cessation since 2000 of the previously - observed growth in atmospheric methane concentration (IPCC, 2007); nor the active 2004 hurricane season; nor the inactive subsequent seasons; nor the UK flooding of 2007 (the Met Office had forecast a summer of prolonged droughts only six weeks previously); nor the solar Grand Maximum of the past 70 years, during which the Sun was more active, for longer, than at almost any similar period in the past 11,400 years (Hathaway, 2004; Solankiet al., 2005); nor the consequent surface «global warming» on Mars, Jupiter, Neptune's largest moon, and even distant Pluto; nor the eerily - continuing 2006 solar minimum; nor the consequent, precipitate decline of ~ 0.8 °C in TS from January 2007 to May 2008 that has canceled out almost all of the observed warming of the 20th century.

On the one side, we know that the level of carbon dioxide in the atmosphere was much lower during past ice - ages than during warm periods, so it is reasonable to expect that an artificially high level of carbon dioxide might stop an ice - age from beginning.