Sentences with phrase «recent atmospheric warming»

Vaughan, D. G. & Doake, C. S. M. Recent atmospheric warming and retreat of ice shelves on the Antarctic Peninsula.

Not exact matches

David Victor, in his recent book, «Global Warming Gridlock» [4], portrays this as one of the worst lessons in designing the Framework Convention that diplomats drew from the Montreal Protocol — the result of a «herd mentality» in the past design of international atmospheric agreements that all followed this same design principle.

The plume is far older than the recent period of atmospheric warming; indeed, at 50 million to 110 million years old, it's older than our species and the West Antarctic Ice Sheet itself.

While natural patterns of certain atmospheric and ocean conditions are already known to influence Greenland melt, the study highlights the importance of a long - term warming trend to account for the unprecedented west Greenland melt rates in recent years.

The most important of these was an apparent mismatch between the instrumental surface temperature record (which showed significant warming over recent decades, consistent with a human impact) and the balloon and satellite atmospheric records (which showed little of the expected warming).

A surprising recent rise in atmospheric methane likely stems from wetland emissions, suggesting that much more of the potent greenhouse gas will be pumped into the atmosphere as northern wetlands continue to thaw and tropical ones to warm, according to a new international study led by a University of Guelph researcher.

Our general circulation model simulations, which take into account the recently observed widespread occurrence of vertically extended atmospheric brown clouds over the Indian Ocean and Asia3, suggest that atmospheric brown clouds contribute as much as the recent increase in anthropogenic greenhouse gases to regional lower atmospheric warming trends.

Recent studies have shown a doubling of stratospheric water vapour, likely from increasing atmospheric heights due to global warming, overshooting thunderstorm tops from stronger tropical cyclones and mesoscale convective systems etc...

If greenhouse gases were responsible for global temperature increases in recent decades, atmospheric physics require that higher levels of our atmosphere would show greater warming than lower levels.

One recent study examining the Palaeocene — Eocene Thermal Maximum (about 55 million years ago), during which the planet warmed 5 - 9 °C, found that «At accepted values for the climate sensitivity to a doubling of the atmospheric CO2 concentration, this rise in CO2 can explain only between 1 and 3.5 °C of the warming inferred from proxy records» (Zeebe 2009).

Clearly atmospheric warming has multiple causes, including CO2 and solar changes, geothermal energy and forest fires etc and all can be at the same time, but research shows solar changes have limited effect, and CO2 is dominating in recent decades and will continue to dominate.

Much of the recent sea ice loss is attributed to warmer sea surface temperatures with southerly wind anomalies a contributing cause [Francis and Hunter, 2007; Sorteberg and Kvingedal, 2006], with thermodynamic coupling leading to associated increases in atmospheric moisture.»

Explanations for the recent «pause» in SST warming include La Niña - like cooling in the eastern equatorial Pacific, strengthening of the Pacific trade winds, and tropical latent heat anomalies together with extratropical atmospheric teleconnections.

If greenhouse gases were responsible for global temperature increases in recent decades, atmospheric physics require that higher levels of our atmosphere would show greater warming than lower levels.

Given that the other important variables (sea surface temps, depth of the warm layer, and atmospheric moisture) are all predicted to increase, it seems hard to make the claim that tropical cyclones will be unchanged, just as it seemed unwise to claim that Lyman et al's «Recent cooling of the upper oceans» meant that climate models had fatal flaws.

There was an eruption of assertions in recent days that the increasing summer retreats and thinning of Arctic Ocean sea ice might be a result not of atmospheric warming but instead all the heat from the recent discovered volcanoes peppering the Gakkel Ridge, one of the seams in the deep seabed at the top of the world.

A recent review article in Nature on this method showed «a warming around 2.2 to 4.8 °C per doubling of atmospheric CO2, which agrees with IPCC estimates».

Here we analyze a series of climate model experiments along with observational data to show that the recent warming trend in Atlantic sea surface temperature and the corresponding trans - basin displacements of the main atmospheric pressure centers were key drivers of the observed Walker circulation intensification, eastern Pacific cooling, North American rainfall trends and western Pacific sea - level rise.

So, we might have been past the warmest period of this most recent interglacial, and beginning a slow, multi-thousand year descent into a new ice age — until we changed the atmospheric composition.

These questions, percolating for a few months in the blogosphere, came to a head with a recent article in The Economist questioning climate sensitivity — the amount of surface warming expected for a doubling of atmospheric carbon dioxide levels.

For more on Alaska's variable, but warming climate, scan «Climate of Alaska: Past, Present and Future,» a recent presentation by Uma S. Bhatt, an associate professor of atmospheric sciences at the University of Alaska, Fairbanks.

In particular, the authors find fault with IPCC's conclusions relating to human activities being the primary cause of recent global warming, claiming, contrary to significant evidence that they tend to ignore, that the comparatively small influences of natural changes in solar radiation are dominating the influences of the much larger effects of changes in the atmospheric greenhouse gas concentrations on the global energy balance.

Our general circulation model simulations, which take into account the recently observed widespread occurrence of vertically extended atmospheric brown clouds over the Indian Ocean and Asia, suggest that atmospheric brown clouds contribute as much as the recent increase in anthropogenic greenhouse gases to regional lower atmospheric warming trends.

A recent publication shows that rising atmospheric CO2 above high altitude Eastern Antarctica is expected to on average cool the surface, not warm it.....

This adjacent plot of 5 - year temperature change versus 5 - year atmospheric CO2 level change is based on the most recent empirical evidence published by the government's GISS / NASA scientists (and they happen to be some of the largest proponents of chicken little global warming calamities).

Ernst Beck has complied tens of thousands of analyses of early measurements of atmospheric CO2, and concludes that CO2 levels were much higher during the 1930's warm period than the generally - accepted levels; CO2 dropped sharply during the cooling from ~ 1946 to ~ 1977; and CO2 increased since 1977 due to the recent warming, and is now at similar levels to the early 1940's.

For example, atmospheric carbon dioxide grew by approximately 30 % during the transition from the most recent cold glacial period, about 20,000 years ago, to the current warm interglacial period; the corresponding rate of decrease in surface ocean pH, driven by geological processes, was approximately 50 times slower than the current rate driven largely by fossil fuel burning.

That one was little - noticed by the world's media, but now its findings may receive more attention, as an independent study by NCAR, published yesterday in Nature Climate Change, has investigated the same subject and reaches a confirming conclusion: in recent years atmospheric warming has been delayed due to increased heat transport to the deeper ocean.

IF GCRs were driving recent warming, you would then have to explain why elevated CO2 wasn't having the radiative effect that atmospheric physics predicts.

DK12 used ocean heat content (OHC) data for the upper 700 meters of oceans to draw three main conclusions: 1) that the rate of OHC increase has slowed in recent years (the very short timeframe of 2002 to 2008), 2) that this is evidence for periods of «climate shifts», and 3) that the recent OHC data indicate that the net climate feedback is negative, which would mean that climate sensitivity (the total amount of global warming in response to a doubling of atmospheric CO2 levels, including feedbacks) is low.

Recent research has yielded insights into the connections between global warming and the factors that cause tornadoes and severe thunderstorms (such as atmospheric instability and increases in wind speed with altitude7, 8).

It would have to be shown that the recent temperature record can be statistically significantly distinguished from the statistically significant warming signal, which can be detected when performing an analysis that uses data over multiple decades, from the mid-1970ies to present, or from the mid-1970ies up to the time, when the alleged change in the behavior of the global atmospheric temperature is supposed to have occurred.

It is arguably one of the most advanced of the seven in its impacts, with a 2011 GRL report putting its warming effect as equivalent to around 30 % of atmospheric anthro - CO2, and the recent report putting albedo loss from arctic sea - ice decline since»79 as providing a forcing equivalent on average to that from 25 % of the anthro - CO2 levels during the period.

Professor Turetsky and her colleagues report that a recent rise in atmospheric methane probably stems from wetland emissions, suggesting that much more will escape into the atmosphere as northern wetlands continue to thaw and tropical ones to warm.

We have a solid 10,000 years of recent climate change to consider, and it shows several periods of greater warming than present, none explained by increased atmospheric CO2, or more obviously, by human activity.

As has been clearly demonstrated with empirical evidence, recent global warming (or lack of) is not the result of increasing atmospheric CO2 levels.

Although there is considerable scientific evidence that limiting warming to 1.5 degrees C is necessary to prevent very dangerous warming, a fact implicit in the recent Paris Agreement in which nations agreed to work to keep warming as close as possible from exceeding 1.5 degrees C additional warming, if the international community seeks to limit warming to 2 degrees C it must assure that global emissions do not exceed the number of tons of CO2 emissions that will raise atmospheric concentrations to levels that will cause warming of 2 degrees C.

... «So, there is at least empirical evidence that increasing temperatures are causing some portion of the recent rise in atmospheric CO2, in which case CO2 is not the only cause of the warming.»

Dr Carter, it should be noted, has only written one scientific paper on atmospheric climate change, which claimed — wrongly as it turned out — to have found that recent global warming was down to natural cycles of water temperatures in the Pacific.

The prominent upward trend in the GM precipitation occurring in the last century and the notable strengthening of the global monsoon in the last 30 yr (1961 — 90) appear unprecedented and are due possibly in part to the increase of atmospheric carbon dioxide concentration, though the authors» simulations of the effects from recent warming may be overestimated without considering the negative feedbacks from aerosols.

Another paper discusses how atmospheric humidity increased during the recent period of pronounced global warming (from about the late 1970s to the present), with a humidity decrease during the cooling / temperature stagnation period of ~ 1940s to the 1970s:

As I have also noted in recent public comments, additional mechanisms have been identified by which changes in atmospheric circulation patterns that may be a result of global warming could be affecting droughts in the American West.

(b) Attributing the recent period of warm winters to an increase in strength of atmospheric circulation (in reference to Scherhag) only pushes the problem one stage back, because one should still have to account for the change in circulation.

Much of the warming in the Arctic in the 20s and 40s, as well as in recent decades was likely due to increased ventilation of ocean heat after sea ice was reduced by intruding warm water and the altered atmospheric circulation.

It appears that increases in atmospheric CO2 (and other GHG's) are contributing approximately 50 % of the recent warming trend on planet earth

Because, as we have demonstrated in the recent article on «equity» and climate change, there are approximately 50 ppm of CO2 equivalent atmospheric space that remain to be allocated among all nations to give the world approximately a 50 % chance of avoiding a 2oC warming and developing nations that have done little to elevate atmospheric CO2 to current levels need a significant portion of the remaining atmospheric space, high emitting developed nations need to reduce their emissions as fast as possible to levels that represent their fair share of the remaining acceptable global budget.

(The only one I can think of, by the only really solidly qualified contrarian, Lindzen, who also claimed that tobacco wasn't linked to lung cancer, came up with an Iris theory that has been thoroughly repudiated (recent studies have in fact continued to strongly show increased atmospheric moisture), but his theory of a significant enough decrease to keep the earth from significantly warming at the same time this radical shift toward lack of global cloud cover (and far more drought everywhere?)

Furthermore, the missing hotspot in the atmospheric warming pattern observed during the last warming period proves that (1) the IPCC climate theory is fundamentally broken, and (2) to the extent that their theory correctly predicts the warming signature of increased carbon dioxide, we know that carbon dioxide definitely did not cause the recent warming (see here for my full explanation of the missing hotspot).

The key question is to what extent atmospheric warming / ice albedo feedback is influencing the recent sea ice decline relative to the natural variability.

Independent evidence from multiple sources suggest — if «real» — that recent warming was all cloud changes associated with decadal changes in ocean and atmospheric circulation.