Sentences with phrase «current holocene»

There are numerous estimates of temperatures since the end of the Pleistocene glaciation, particularly during the current Holocene epoch.

A majority voted in favor of designating the Anthropocene as an «epoch / series,» according to the working group, which would mean that the current Holocene epoch, which began about 11,700 years ago, has terminated.

As for interglacials, the present is significantly cooler than much of the first 9,000 years of the current Holocene.

Due to the way in which these various cycles have been relative constant over the last 35 million years, the earth has settled into a relatively recent cycle of approximately 100,000 year long declining climates and ice ages, and brief 12,000 - 18,000 year long warm spells we call inter-glacial periods like our current Holocene.

Another example is this paper which discusses the cause of the Younger Dryas abrupt climatic change which interrupted the current Holocene interglacial returning the planet back to the glacial phase.

A new working group of experts has now been established to gather all the evidence which would support recognising it as the successor to the current Holocene epoch.

However, we know that severe and abrupt climate shifts of global extent have occurred (infrequently) during glaciations, and almost never during warmer interglacial periods such as the current Holocene.

Such states may have prevailed in the distant past, but there is nothing about the current Holocene climate to suggest that more than a single equilibrium is within range — we are not close to a new glaciation nor a new «hothouse climate» (although the latter might become possible if continued greenhouse gas emissions were to remain unmitigated for a prolonged interval).

Anyway, today we try to explain the exact opposite: how northern hemisphere ice ages can quite suddenly weaken — at least in case of the last one, which had its cold peak around 18,000 years ago, after which atmospheric CO2 levels «suddenly» (over a millennium or so) rose by 30 per cent, and temperatures started to climb closer * to our current Holocene values.

The current Holocene interglacial period might last up to another 3,000 years before the Earth plunges into another glaciation.

Why should warming during the current Holocene Interglacial be significantly different / less than during the previous Eemian Interglacial (MIS5e), when sea levels were, per the IPCC's own comments, above modern levels or for that matter above the purported mid-Holocene highstand?

Another devastating cycle of cooling and warming followed: a sudden, brutal cold snap called the Younger Dryas around 13,000 years ago, followed by rising temperatures in the current Holocene Epoch.

Instead, the fossil record indicates they vanished during the Earth's glacial - interglacial transition, which occurred about 12,000 years ago and led to much warmer conditions and the start of the current Holocene period.

Not exact matches

They recommended that we officially mark the end of the Holocene, the current epoch, and enter the Anthropocene.

But some researchers have argued that the transition from the frigid climatic period known as the Last Glacial Maximum (LGM)-- about 20,000 to 25,000 years ago — to the current warm Holocene Epoch brought habitat changes that killed off the mammoths with little or no help from humans.

Biologists call it the Sixth Great Extinction, or the Holocene extinction event, after our current geologic time period.

Just for the sake of illustration, though, here's one scenario where higher Holocene variability could go along with lower climate sensitivity: Suppose that some unknown stabilizing mechanism makes the real world less sensitive to radiative forcing than our current models.

Bottom - water temperature and current velocities have also fluctuated in relation to decadal — millennial scale climatic changes during the last de-glaciation and Holocene (Bianchi and McCave, 1999; Marchitto and deMenocal, 2003; Farmer et al., 2011; Cronin et al., 2012).

does fit the temperature trend to an acceptable level, if one should reduce the sensitivity for CO2 / aerosols far enough... Current models also can reproduce other transitions (LGM - Holocene) with a reasonable accuracy, but this is mainly in periods where there is a huge overlap between temperature (as initiator) and CO2 / CH4 levels (as feedback).

The current era (at least under present definitions), known as the Holocene, began about 11,700 years ago, and was marked by warming and large sea level rise coming out of a major cool period, the Younger Dryas.

Because our current interglacial (the Holocene) has already lasted approximately 12,000 years, it has led some to claim that a new ice age is imminent.

Current spatial coverage, temporal resolution and age control of available Holocene proxy data limit the ability to determine if there were multi-decadal periods of global warmth comparable to the last half of 20th century.

We use measured global temperature and Earth's measured energy imbalance to determine the atmospheric CO2 level required to stabilize climate at today's global temperature, which is near the upper end of the global temperature range in the current interglacial period (the Holocene).

The Holocene (/ ˈ h ɒ l ə ˌ s iː n, ˈ h oʊ - /) is the current geological epoch.

«In other words, the rate of change is much greater than anything we've seen in the whole Holocene,» referring to the current geologic time period, which began around 11,500 years ago.

The current picture of Holocene climate variations is based not just on tree ring data, but on glacial mass balance and a wide variety of other proxy data.

Also, you need to consider the reality that all our current food infrastructure has been built during the relative radiative forcing of the Holocene and now we have altered that forcing.

Just for the sake of illustration, though, here's one scenario where higher Holocene variability could go along with lower climate sensitivity: Suppose that some unknown stabilizing mechanism makes the real world less sensitive to radiative forcing than our current models.

does fit the temperature trend to an acceptable level, if one should reduce the sensitivity for CO2 / aerosols far enough... Current models also can reproduce other transitions (LGM - Holocene) with a reasonable accuracy, but this is mainly in periods where there is a huge overlap between temperature (as initiator) and CO2 / CH4 levels (as feedback).

Further, Vostok suggests that within centuries, Global Temperatures will then plummet by some 10 °C in just a few thousand years, ending the current stable - temperature Holocene Epoch in which human civilisation flourished.

But putting the evidence together indicates an overall magnitude of change at least as large as that which ushered in the Holocene, our current geological epoch, and most other epochs.

Our current climate in much closer to the coolest level of the Holocene than the warmest (Holocene Optimim ~ 8,000 years ago).

The original topic of the conversation was whether Romm's graph made a convincing case for the current warming being unusual and concerning in the context of Holocene history.

... According to the marine records, the Eemian interglacial (William: Eemain is the name of the last interglacial period, the current interglacial period is called the Holocene) ended with a rapid cooling event about 110,000 years ago (e.g., Imbrie et al., 1984; Martinson et al., 1987), which also shows up in ice cores and pollen records from across Eurasia.

Yet, within a few thousand years, global temperatures rose by around 3 - 8C, causing the ice to thaw and the world to enter its current geological period, the Holocene.

In other words, aim to get temperatures back under the Holocene maximum of 0.5 ºC, which implies a level of greenhouse gases below 320 parts per million (ppm) of atmospheric carbon dioxide (CO2), compared to the current level of 405 ppm.

In this case, the magnitude and duration of global temperature excursion above the natural range of the current interglacial (Holocene) could be limited and irreversible climate impacts could be minimized.

There is observational evidence of 23 cycles of warming and cooling (nine of the cycles occurred in the current interglacial period, the Holocene).

The current interglacial period (known as the «Holocene») started 10,000 - 15,000 years ago, and the previous interglacial (known as the «Eemian») occurred about 115,000 - 130,000 years ago.

Even as shorter trends, CO2 content in atmosphere follow global temperature trends and not visa versa, for instance during glasials and interglasial, including even the current interglasial Holocene, as I already in my comment above stated concerning the recent increase of CO2 content in atmosphere.

Within this far more recent part of our planet's history the current disturbance of the radiative balance is unique at least over the last 20,000 years, stretching the entire Holocene up to the point where the Milankovitch cycles thought it fit to end the last ice age.

``... the three researchers write that they «provide experimental support for suggestions and simulation studies predicting that reductions in CO2 alone could have led to loss of tree cover in grassy environments in the last glacial (Bond et al., 2003; Harrison and Prentice, 2003),» and they say that «the large increases in CO2 from industrial emissions over the last century would now favor trees at the expense of grasses,» which conclusion is supported by palaeo - records that indicate that «trees disappeared from current savanna sites in South Africa during the Last Glacial Maximum (Scott, 1999), re-appeared in the Holocene, and have rapidly increased over the last half century,»... Read More

The practical and profitable path is to build on this wonderful tool Marcott has developed, beat the flaws out of it, and use it to validate Holocene - spanning GCMs (now that we can contemplate such as technically feasible in the near future) by comparing their outputs — which modellers can make as granular as computers can handle, thereby answering such questions as how probable is it the current rise is the fastest in the Holocene period — through a filter that derives the probable curves of proxies.

The Marcott et al. conclusions that «Current global temperatures of the past decade... are warmer than during ~ 75 % of the Holocene temperature history» and «Global mean temperature for the decade 2000 - 2009....

we conclude that the current decadal mean temperature in Greenland has not exceeded the envelope of natural variability over the past 4000 years, a period that seems to include part of the Holocene Thermal Maximum.

We are about 10,000 years into the current warm period called the Holocene.

In brief, Earth's current 2.6 - million year Pleistocene Era is defined by cyclically recurring Ice Ages averaging c. 102,000 years, interspersed with 12,250 - year remissions such as our fading Holocene Interglacial Epoch.

An overview of the geological record of sea level rise is provided, with a focus on Holocene (the current interglacial).

After the Holocene Optimum ended about 5,000 years ago and sea level rise slowed, California's current rate of coastal erosion decreased to about 10 to 30 cm / year.

I am pretty sure that the MWP was at least as warm and maybe even warmer than today, as good as the Roman WP was warmer and the Holocene Climate optimum of 6,000 years ago was warmer... The MWP had a CO2 level about 6 ppmv higher than the LIA, that is all you can expect as increase in the atmosphere from the current warm period.