Sentences with phrase «by natural variability over»

Not exact matches

Some experiments were considered quirky by 19th century standards, but the work provided data supporting Darwin's notions about trait variability in a population and how natural selection drives changes in populations over time.

He writes: «the data of landfalling hurricanes in the U.S. is less than a tenth of a percent of the data for global hurricanes over their whole lifetimes», and shows that from such a small subset of data and given the amount of natural variability, there is no way you would be able to detect a trend by now.

By looking at the signatures of climate change in precipitation intensity and comparing that to the internal variability and the observation, the researchers conclude that the probability of intense precipitation on any given day has increased by 7 percent over the last 50 years — well outside the bounds of natural variabilitBy looking at the signatures of climate change in precipitation intensity and comparing that to the internal variability and the observation, the researchers conclude that the probability of intense precipitation on any given day has increased by 7 percent over the last 50 years — well outside the bounds of natural variabilitby 7 percent over the last 50 years — well outside the bounds of natural variability.

Over the weekend I noticed a clever new effort to visualize how natural climate variability interacts with the heating effect from accumulating greenhouse gases — made by Teddy TV and the animator Ole Christoffer Haga for the 10 - part math series Siffer on Norway's NRK channel *:

It is quite clear that the perturbation that we are currently imposing is already large, and will be substantially larger, by up to an order of magnitude, than any plausible natural variability over this time scale.

My experience with extremes and detection and attribution of an anthropogenic signal in those is that only by averaging the behavior of extremes (both temperature extremes and precipitation extremes) over large geographical areas (continental or barely sub-continental) we have been able to see something outside of natural variability.

I get the impression it was pretty well expected that at this point the overall trend should still subject to significant modulation over short periods by natural variability.

However, from 1971 to 2020, they found that the average rate of change over North America, for example, was about 0.3 degrees Celsius per decade - that's higher than can be accounted for by natural variability alone.

Skeptical101 # 14 My interpretation and synopsis of the considerable technical detail and references provided by Tom Curtis # 15 & One Planet # 16, # 17 is that your»... not use it as an argument to support AGW» is correct if used over periods in which short term natural variability influences the trend strongly (< 30 years was mentioned sometimes) and, in particular, the models are not able to predict the ENSO conditions at all well.

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 variabilitBy 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 variabilitby a combination of anthropogenic and natural forcing and internal variability.

Lead author Dr Debbie Polson, of the University of Edinburgh's School of GeoSciences, said: «This study shows for the first time that the drying of the monsoon over the past 50 years can not be explained by natural climate variability and that human activity has played a significant role in altering the seasonal monsoon rainfall on which billions of people depend.»

Brought to You by SEPP (www.SEPP.org) The Science and Environmental Policy Project ################################################### Quote of the Week: «a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over considerable time periods.»

Climate change is defined by the Convention as «change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods» (article 1 (2)-RRB-.

Over the last 15 years, however, a large number of studies changed this view by providing robust evidence for the existence of significant natural climate variability.

There is no mechanism proposed by which internal natural variability can lead to any warming that does not average out over decades, and even then its magnitude can't be more than tenths of a degree.

In response to claims made by Bob Carter that the Intergovernmental Panel on Climate Change had not uncovered evidence that global warming was caused by human activity, a former CSIRO climate scientist stated that Bob Carter was not a credible source on climate change and that «if he [Carter] has any evidence that [global warming over the past 100 years] is a natural variability he should publish through the peer review process.»

... [M] ost of the trends observed since satellite climate monitoring began in 1979 CE can not yet be distinguished from natural (unforced) climate variability, and are of the opposite sign [cooling] to those produced by most forced climate model simulations over the same post-1979 CE interval.»

The latter result shows that natural internal variability, as simulated by current climate models, is a highly unlikely explanation for the observed lower tropospheric warming over the satellite era»

Research suggests that long - term drying trends over southern Australia can not be explained by natural variability alone.

The fact that there has on any basis been little further warming over the course of the last 10 to 15 years over and above that which had already occured by the mid / late 19902 suggests that recent extreme weather events are not the consequence of additional warming (there having been all but none these past 15 years) and therefore must be due to natural variability of weather events in an ever changing and chaotic world in which we live.

However, changes in climate at the global scale observed over the past 50 years are far larger than can be accounted for by natural variability.

It is also defined by the United Nations Convention on Climate Change as «change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods»

He said, «The pattern over the last 100 years has been characterized by overall warming, with signals of natural climate variability.»

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.»

CAGW die - hards are scrambling to find a rationalization for this «lack of warming» (it's Chinese aerosols, the warming is hidden somewhere, maybe in the ocean, it's being over shadowed by natural variability, etc., etc.), but these all sound pretty weak and contrived.

Although the recent drought may have significant contributions from natural variability, it is notable that hydrological changes in the region over the last 50 years can not be fully explained by natural variability, and instead show the signature of anthropogenic climate change.

Judith writes: «Comparing the model temperature anomalies with observed temperature anomalies, particularly over relatively short periods, is complicated by the acknowledgement that climate models do not simulate the timing of ENSO and other modes of natural internal variability...»

Comparing the model temperature anomalies with observed temperature anomalies, particularly over relatively short periods, is complicated by the acknowledgement that climate models do not simulate the timing of ENSO and other modes of natural internal variability; further the underlying trends might be different.

The climate is chaotic, nudged over the long - term by specific unique combinations for forcing, with a lot of wiggly natural variability «noise» over the shorter time frames.

Gavin said upfront: «By looking at the signatures of climate change in precipitation intensity and comparing that to the internal variability and the observation, the researchers conclude that the probability of intense precipitation on any given day has increased by 7 percent over the last 50 years — well outside the bounds of natural variability»By looking at the signatures of climate change in precipitation intensity and comparing that to the internal variability and the observation, the researchers conclude that the probability of intense precipitation on any given day has increased by 7 percent over the last 50 years — well outside the bounds of natural variability»by 7 percent over the last 50 years — well outside the bounds of natural variability».

The natural variability may be further reduced by averaging over more realisations, over longer time intervals, and by averaging in space, although averaging also affects the information content of the result.

Dole compared his team's findings to trying to hear a quiet conversation underneath the roar of a noisy fan: a summertime signal due to climate change over western Russia was drowned out by the much larger climate «noise,» or variability, resulting from natural processes.

The met office are also more open to the idea of considerable natural variability than they were five years ago when their web site stated that climate was virtually constant before mans input.In that respect opinion is moving towards that expounded by lamb which has been somewhat sidelined over the past thirty years.