Sentences with phrase «cycles over timescales»

Ice core records are rich archives of the climate history during glacial - interglacial cycles over timescales of up to ~ 800 kyr before the current age.

Not exact matches

Cycles that drive changes in the ocean's chemistry and organisms take place over hours, days, seasons, years and even decades — timescales NEPTUNE can track.

But the duration of an SKR cycle later proved to vary by several minutes over the years, whereas a planet's rotational speed should remain nearly constant on such short timescales.

Earth has a carbon - silicate cycle that acts like a thermostat over geological timescales.

For carbon perturbations that take place over shorter timescales, the pace of carbon - cycle changes will not matter; instead, the size or magnitude of the change will determine the likelihood of an extinction event.

We recently extended this record to approximately 120,000 years BP in order to track vegetation change over a full glacial cycle at millennial to orbital timescales.

In a paper published in Science Advances, he proposes that mass extinction occurs if one of two thresholds are crossed: For changes in the carbon cycle that occur over long timescales, extinctions will follow if those changes occur at rates faster than global ecosystems can adapt.

This means that there were large - scale changes in the carbon cycle over a short geological timescale of several tens of thousands of years.

Re # 8, any changes in climate over glacial - interglacial timescales have to take into account an additional component: the biogeochemical cycling of atmospheric gases.

Re glacial cycle CO2 and temp correlation, it is useful to remember that the timescale of that record is 100's of thousands of years, where as the CO2 rise today has occurred over ~ 100.

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.

However, there do also seem to be lunar and solar cycles which take place over longer timescales, e.g., the 18.6 year lunar cycle.

Excellent work as usual, Bob, but you won't be surprised that I'm still trying to see how your ENSO material can be worked into the climate cycling from MWP to LIA to date without some other force altering the relative strengths of El Nino and La Nina over longer timescales than the multidecadal.

Scientists were aware tidal energy varied in the distant past, but the new study suggests there is a super-tidal cycle occurring over geologic timescales and linked to tectonic movement.

I wrote to the BBC at the time pointing out that the audience was likely to have been severely misled by this question, that the warming over the previous 16 years reached a conventional threshold of statistical significance (p < 0.05), and that over a short timescale natural causes of variability (ENSO, volcanoes, the solar cycle) tend to predominate, so the short answer is «15 years is too small a sample to demonstrate statistical significance.»

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).