Sentences with phrase «temperature over a timescale»

As LST closely tracks air temperatures over the instrumental period, we can also infer that air temperatures in this region of East Africa varied in concert with the global average and thus were controlled primarily by the major forcings influencing temperatures over this timescale, both natural (solar radiation, volcanism) and anthropogenic (greenhouse - gas emissions; refs 19, 20).

This study, which was supported by the U.S. National Science Foundation, is the first to analyze long - term trends in rainfall and surface air temperature over a timescale of nearly an entire century, the study's lead author, Natalie Thomas, a doctoral candidate in atmospheric and oceanic science at the University of Maryland, told Live Science.

Not exact matches

Weathering of rocks can control Earth's temperature over geologic timescales, new geochemical data suggest.

CO2 provides only a minor effect in the obliquity and precession timescale band, but over 30 % of the forcing in the 100 kyr band, so it is a key forcing agent that allows us to explain the magnitude of glacial - interglacial temperature variations.

Atmospheric concentrations of carbon dioxide gradually returned to near - background levels over a similar timescale to global temperatures.

Climate scientists would say in response that changes in ocean circulation can't sustain a net change in global temperature over such a long period (ENSO for example might raise or lower global temperature on a timescale of one or two years, but over decades there would be roughly zero net change).

Operating on an unhurried timescale the gum responds to material friction, temperature and humidity as it spreads across a surface, sluggishly following a viscous trajectory that transforms the sculpture over months.

It's not necessarily the case that relative trajectories of OHC and surface temperature have to be congruent over these long timescales.

Therefore it cant drive long term temperature increases over century timescales, only short term fluctuations.

Of course, on a timescale of one decade the noise in the temperature signal from internal variability and measurement uncertainty is quite large, so this might be hard to determine, though tamino showed that five year means show a monotonic increase over recent decades, and one might not unreasonably expect this to cease for a decade in a grand solar minimum scenario.

That is equivalent to saying that temperatures aren't rising over longer timescales.

It appears that Ghil, and others specifically warn against the use of MEM and temperature data: «Instrumental temperature data over the last few centuries do not seem, for instance, to determine sufficiently well the behavior of global or local temperatures to permit a reliable climate forecast on the decadal timescale by this SSA - MEM method.»

Under most scenarios of late 20th century and future anthropogenic radiative forcing, a steady, rather than accelerating, rise in global and hemispheric mean temperature is predicted over timescales of decades.

Over very long time periods such that the carbon cycle is in equilibrium with the climate, one gets a sensitivity to global temperature of about 20 ppm CO2 / deg C, or 75 ppb CH4 / deg C. On shorter timescales, the sensitivity for CO2 must be less (since there is no time for the deep ocean to come into balance), and variations over the last 1000 years or so (which are less than 10 ppm), indicate that even if Moberg is correct, the maximum sensitivity is around 15 ppm CO2 / deg C. CH4 reacts faster, but even for short term excursions (such as the 8.2 kyr event) has a similar sensitivOver very long time periods such that the carbon cycle is in equilibrium with the climate, one gets a sensitivity to global temperature of about 20 ppm CO2 / deg C, or 75 ppb CH4 / deg C. On shorter timescales, the sensitivity for CO2 must be less (since there is no time for the deep ocean to come into balance), and variations over the last 1000 years or so (which are less than 10 ppm), indicate that even if Moberg is correct, the maximum sensitivity is around 15 ppm CO2 / deg C. CH4 reacts faster, but even for short term excursions (such as the 8.2 kyr event) has a similar sensitivover the last 1000 years or so (which are less than 10 ppm), indicate that even if Moberg is correct, the maximum sensitivity is around 15 ppm CO2 / deg C. CH4 reacts faster, but even for short term excursions (such as the 8.2 kyr event) has a similar sensitivity.

I was reacting to Chris Colose comment re: «Models all produce natural variability, many of which show temperature flatlines over decadal timescales.»

Models all produce natural variability, many of which show temperature flatlines over decadal timescales, and given the wide importance of natural variability over < 10 year time scales and uncertain forcings, one can absolutely not claim that this is inconsistent with current thinking about climate.

It would require a much stronger relationship of temperature driving CO2 than occurred during the ice age — interglacial oscillations (and it is also important to remember that those changes occurred over much longer timescales too... which is the presumed reason why there is a several hundred year lag time between temperatures starting to rise or fall and CO2 starting to rise or fall).

But, they do suggest that there is a lot of natural temperature variability over timescales of centuries.

We are talking about temperature changes today over a fifty year (or shorter) period, and we have absolutely no way to look at changes in the «geological past» on this fine of a timescale.

eCast's web - based interface allows easy access to meaningful forecast ranges, timescales and visualizations for maximum and minimum temperatures, as well as the probability of precipitation, over the next 10 - days.

«We build on this insight to demonstrate directly from ice - core data that, over glacial — interglacial timescales, climate dynamics are largely driven by internal Earth system mechanisms, including a marked positive feedback effect from temperature variability on greenhouse - gas concentrations.»

Global Temperature is an example of a bulk property, and it does indeed average out over sufficient time scales; hence showing that whatever chaos, spatio - temporal or otherwise, is present in the system on short timescales it does not affect our longer term predictions.

It is hard to argue with the evidence — the climate system as a whole is not chaotic, but rather harbors chaotic elements that average out over multidecadal timescales, revealing an underlying temperature trend.

All the data that I'm aware clearly shows that models predicting or hindcasting global temperature trends do far better at 30 year timescales than annually or over only a few years.

It is defined as the amount of warming expected if carbon dioxide (CO2) concentrations doubled from pre-industrial levels and then remained constant until Earth's temperature reached a new equilibrium over timescales of centuries to millennia.

This would include the volume of phase space occupied by chaotic attractors, the consequent amplitude of temperature fluctuations, and the timescale over which any averaging might occur.

Hasn't the latest Arctic research (e.g., Kobashi, et al., 2010; Rørvik, et al., 2009) shown that significant variability of high latitude temperatures on > 100 + year timescales have been the natural course of events over the last 1,000 to 1,500 years, all without benefit of increasing or decreasing levels of atmospheric CO2?

Reanalysis data from 1948 to 2005 indicate weakening westerlies over this time period, a trend leading to relatively cooler temperatures on the east slope over decadal timescales.

«Over relatively short, non-climate timescales (less than 20 - 30 years), these patterns of natural variability can lead to all kinds of changes in global and regional near - surface air temperature: flat, increasing, or even decreasing trends,»

Components of the Earth's climate system that vary over long timescales, such as ice sheets and vegetation, could have an important effect on this temperature sensitivity, but have often been neglected.

Climate scientists would say in response that changes in ocean circulation can't sustain a net change in global temperature over such a long period (ENSO for example might raise or lower global temperature on a timescale of one or two years, but over decades there would be roughly zero net change).

«Based on their results, the researchers conclude that the Arctic Ocean has a previously unrecognized high sensitivity to changes of the freshwater input over multiple timescales, which is manifested in large temperature excursions of the intermediate water layers.»

However, the expectation is that if we average over a sufficiently long timescales (decades) that the response will be roughly linear (I'm thinking specifically about temperature change, and changes to the hydrological cycle).

In any case, a» temporary, source of over 3 billion tonnes» has absolutely no effect on the total CO2 level and hence on temperatures which react with a much longer timescale, so the only reasonable and quick answer to Carl would have been: No, of course!!!

However, one should hesitate to draw conclusions empirically over as short a period as 60 years: for it is the cry - babies» contention that temperature feedbacks operate over various timescales out to 1000 - 3000 years (Solomon et al., 2009).

Temperature increases in the thermocline occur on the decadal timescale whereas, over most of the abyss, it is the millennial time scale that is relevant, and the strength of MOC in the channel matters for the intensity of heat uptake.

But the long term trend is up, and in the physical world, such trends towards increasing (or decreasing) temperatures over climatologically relevant timescales do not happen without a reason.