Sentences with phrase «estimate warming over»

To estimate warming over the entire 21st century, scientists have to make assumptions about what happens beyond the INDCs.

While we are hesitant to extrapolate from very short data series (always a dubious procedure) it is entirely plausible that reduction in low cloud over the period could conservatively be estimated to have increased heating at Earth's surface by 5 - 10 Wm - 2, an amount more than sufficient to account for all the estimated warming over the period.

Not exact matches

Here's more: Coral reefs the world over are dying as warmer sea water bleaches them to death — by some estimates, this whole amazing ecosystem, this whole lovely corner of God's brain, may be extinct by mid-century.

Schmidt's rough estimate, which he posted on Twitter, is based on the extraordinary and unprecedented warming over the past 12 months, during which time global surface temperatures have shot past the 1 °C above pre-industrial level.

In one study published in Geophysical Research Letters in 2007, scientists at the Max Planck Institute for Meteorology in Hamburg, Germany, estimated the mass redistribution resulting from ocean warming would shorten the day by 120 microseconds, or nearly one tenth of a millisecond, over the next two centuries.

«An important result of this paper is the demonstration that the oceans have continued to warm over the past decade, at a rate consistent with estimates of Earth's net energy imbalance,» Rintoul said.

Although the earth has experienced exceptional warming over the past century, to estimate how much more will occur we need to know how temperature will respond to the ongoing human - caused rise in atmospheric greenhouse gases, primarily carbon dioxide.

Rather than using complex computer models to estimate the effects of greenhouse - gas emissions, Lovejoy examines historical data to assess the competing hypothesis: that warming over the past century is due to natural long - term variations in temperature.

But the change from 2004 to 2007 in the sun's output of visible light, and the attendant warming at Earth's surface of 0.1 watt per square meter, is roughly equivalent to the overall forcing of the sun on the climate over the past 25 years — estimated by the U.N. Intergovernmental Panel on Climate Change to be an additional 0.12 watt per square meter.

This so - called constant - composition commitment results as temperatures gradually equilibrate with the current atmospheric radiation imbalance, and has been estimated at between 0.3 °C and 0.9 °C warming over the next century.»

al. — May 2013 Global Warming and Neotropical Rainforests: A Historical Perspective... Our compilation of 5,998 empirical estimates of temperature over the past 120 Ma indicates that tropics have warmed as much as 7 °C during both the mid-Cretaceous and the Paleogene.....

Indeed, the main quandary faced by climate scientists is how to estimate climate sensitivity from the Little Ice Age or Medieval Warm Period, at all, given the relative small forcings over the past 1000 years, and the substantial uncertainties in both the forcings and the temperature changes.

Since 1950, the volcanic forcing has been negative due to a few significant eruptions, and has offset the modestly positive solar forcing, such that the net natural external forcing contribution to global warming over the past 50 years is approximately zero (more specifically, the authors estimate the natural forcing contribution since 1950 at -10 to +13 %, with a most likely value of 1 %).

Keep in mind that the Paris study, looking at all the science of global warming, will only project a «best estimate» that temperatures will rise by 3 Celsius (5.4 Fahrenheit) by 2100 over pre-industrial levels.

The inverse estimates summarised in Table 9.1 suggest that to be consistent with observed warming, the net aerosol forcing over the 20th century should be negative with likely ranges between — 1.7 and — 0.1 W m — 2.

In the original article Angela did write: «This effect, called the permafrost carbon feedback, is not present in the global climate change models used to estimate how warm the earth could get over the next century.»

Perhaps we also need a market to estimate the amount of uncertainty in the estimate of warming and / or perhaps the amount of natural variability over a multi-decadal period.

The best estimate of the human induced contribution to warming is similar to the observed warming over this period.

This effect, called the permafrost carbon feedback, is not present in the global climate change models used to estimate how warm the earth could get over the next century.

If only half the warming over 1976 - 2000 (linear trend 0.18 °C / decade) was indeed anthropogenic, and the IPCC AR5 best estimate of the change in anthropogenic forcing over that period (linear trend 0.33Wm - 2 / decade) is accurate, then the transient climate response (TCR) would be little over 1 °C.

The best estimate of the human - induced contribution to warming is similar to the observed warming over this period.

Item 8 could be confusing in having so many messages: «It is extremely likely that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic increase in greenhouse gas... The best estimate of the human - induced contribution to warming is similar to the observed warming over this period....

The actual prevailing view of the paleoclimate research community that emerged during the early 1990s, when long - term proxy data became more widely available and it was possible to synthesize them into estimates of large - scale temperature changes in past centuries, was that the average temperature over the Northern Hemisphere varied by significantly less than 1 degree C in previous centuries (i.e., the variations in past centuries were small compared to the observed 20th century warming).

The problem here is that estimates of changes in sea surface temperature and the depth of the warm mixed layer might be very unreliable, since the general behavior of the Atlantic circulation is only now being directly observed — and the most recent findings are that flow rates vary over a whole order of magnitude:

Extrapolating from their forest study, the researchers estimate that over this century the warming induced from global soil loss, at the rate they monitored, will be «equivalent to the past two decades of carbon emissions from fossil fuel burning and is comparable in magnitude to the cumulative carbon losses to the atmosphere due to human - driven land use change during the past two centuries.»

-- S09 show fast warming in West Antarctica, with a central estimate over twice its lower 95 % confidence limit (0.20 ± 0.09, using our geographical definitions).

The revelations fueled charges that all that asphalt and the like was inflating temperature estimates and thus conclusions that the nation's climate was warming over all.

We conclude that the fact that trends in thermometer - estimated surface warming over land areas have been larger than trends in the lower troposphere estimated from satellites and radiosondes is most parsimoniously explained by the first possible explanation offered by Santer et al. [2005].

Indeed, the main quandary faced by climate scientists is how to estimate climate sensitivity from the Little Ice Age or Medieval Warm Period, at all, given the relative small forcings over the past 1000 years, and the substantial uncertainties in both the forcings and the temperature changes.

Millar et al. wrote the confusing sentence: «in the mean CMIP5 response cumulative emissions do not reach 545GtC until after 2020, by which time the CMIP5 ensemble - mean human - induced warming is over 0.3 °C warmer than the central estimate for human - induced warming to 2015».

[T] here have now been several recent papers showing much the same — numerous factors including: the increase in positive forcing (CO2 and the recent work on black carbon), decrease in estimated negative forcing (aerosols), combined with the stubborn refusal of the planet to warm as had been predicted over the last decade, all makes a high climate sensitivity increasingly untenable.

However even the moderate scenarios which have eventual stabilisation give more warming than 0.8 C. Even in the extremely unlikely event that there is no further growth in emissions, the current planetary energy imbalance (estimated to be almost 1W / m2)(due to the ocean thermal inertia) implies that there is around 0.5 C extra warming already in the pipeline that will be realised over the next 20 to 30 years.

Gavin Schmidt writes, «He (Crichton) also gives us his estimate, ~ 0.8 C for the global warming that will occur over the next century and claims that, since models differ by 400 % in their estimates, his guess is as good as theirs.

What is your ’50 percent probability» estimate for global warming in the lower troposphere over the next 100 years?

What is obvious is that including the data of the past few years pushes the estimates of climate sensitivity downward, because there was little warming over the past decade despite a larger greenhouse gas forcing.

The «Clean Sky» initiative, reports Israel21c is the largest European research project ever and is designed to tackle global warming — with a budget estimated to reach over 1.6 billion Euros, the project «aims to radically improve the impact of air transport on the environment with the goal of eliminating environmental pollution by reducing greenhouse gases.»

But Zycher points to excursions from 1910 - 1940 and 1940 - 1970 (a warming then a cooling that climate models do not collectively capture) as evidence of their inability to estimate response to forcing over longer periods.

Estimates typically project the amount of warming from a doubling of CO2 concentrations over the pre-industrial (year 1750) level of 280 parts per million (ppm).

Large uncertainties associated with estimates of past solar forcing (Section 2.7.1) and omission of some chemical and dynamical response mechanisms (Gray et al., 2005) make it difficult to reliably estimate the contribution of solar forcing to warming over the 20th century.

Notice, for instance, that one account of the consensus (more accurate than Grimes's) holds that «most of the warming in the second half of the twentieth century has been caused by man», and does not exclude the majority of climate sceptics, who typically argue that the IPCC over estimates climate sensitivity.

Estimates of climate sensitivity tell us that the Earth will eventually warm somewhere between 1.5 °C and 4.5 °C if we double the amount of carbon dioxide in the atmosphere over pre-industrial levels.

The IPCC stated with 95 % confidence that most of the global warming since 1950 is human - caused, with a best estimate that 100 % is due to humans over the past 60 years.

By comparing modelled and observed changes in such indices, which include the global mean surface temperature, the land - ocean temperature contrast, the temperature contrast between the NH and SH, the mean magnitude of the annual cycle in temperature over land and the mean meridional temperature gradient in the NH mid-latitudes, Braganza et al. (2004) estimate that anthropogenic forcing accounts for almost all of the warming observed between 1946 and 1995 whereas warming between 1896 and 1945 is explained by a combination of anthropogenic and natural forcing and internal variability.

It's estimated that to make a substantial difference to global warming huge expanses of land would have to be given over to growing biomass crops.

Because we can now accurately estimate the 20th century CO2 warming by multiplying the known CO2 forcing over the 20th century by the claimed climate sensitivity of 1.6 - 1.7 C.

This value is the government's best estimate of how much society gains over the long haul by cutting each ton of the heat - trapping carbon - dioxide emissions scientists have linked to global warming.

In SPM we can read also «The best estimate of the human - induced contribution to warming is similar to the observed warming over this period.»

The Arctic has been warming at more than twice the rate of the globe as a whole, with average temperatures today 5.4 °F (3 °C) above what they were at the beginning of the 20th century, compared to an estimated global average of 1.8 °F (1 °C) over the same time.

It is no surprise there is significant disagreement over the amount of warming estimated — as James Hansen and the Goddard Institute for Space Studies explain7, there is no clear definition of what we mean by absolute surface air temperature and wide variation in the estimated mean surface temperature of the planet.

Despite the rhetoric, the best available estimate of the damage we face from unconstrained global warming is not «global destruction,» but is instead costs on the order of 3 percent of global GDP in a much wealthier world well over a hundred years from now.