Sentences with phrase «climate over long time scales»

Not exact matches

Countering a widely - held view that thawing permafrost accelerates atmospheric warming, a study published this week in the scientific journal Nature suggests arctic thermokarst lakes are «net climate coolers» when observed over longer, millennial, time scales.

When all (or most) of the factors that contribute to climate are considered, it is obvious that cyclical patterns will result over long time scales.

If we decide, as Lomborg suggests, to focus exclusively on a handful of top priorities at the expense of all others, especially those that are more complex and operate over longer time scales, such as Climate Change, we are doing little more than arranging the Titanic's proverbial deck - chairs.

Back in 2001, Peter Doran and colleagues wrote a paper about the Dry Valleys long term ecosystem responses to climate change, in which they had a section discussing temperature trends over the previous couple of decades (not the 50 years time scale being discussed this week).

Over even longer time scales (hundreds of years) there are a number of paleo - records that correlate with records of cosmogenic isotopes (particularly 10Be and 14C), however, these records are somewhat modulated by climate processes themselves (the carbon cycle in the case of 14C, aerosol deposition and transport processes for 10Be) and so don't offer an absolutely clean attribution.

But this human adaptation time scale may be longer than the time over which climate change affects storms, so that comparatively small changes in the frequency of generational events can have large social consequences.

Temperatures over that period varied probably by less than 2 deg C, so the climate during which we developed our way of life was very consistent when compared with the long - term geological time scale.

The oceans influence climate over long and short time - scales.

The strength of teleconnections and the way they influence surface climate also vary over long time scales.

These results correspond to independently deduced Phanerozoic paleoclimates and support the notion that the atmospheric CO2 greenhouse mechanism is a major control on climate over very long time scales.

It's true that climate varies naturally over both short and long time - scales, but it's possible to distinguish natural climate change from human caused climate change.

It doesn't mean that there can't be any natural variability that appears as wobbles in the temperature record (or in other climate variables), masking the multi-decadal temperature trend over a time scale shorter than 20 years with the effect that the longer term trend is not statistically detectable in the time series, if one chooses the time period only short enough.

Jan Perlwitz says:» It doesn't mean that there can't be any natural variability that appears as wobbles in the temperature record (or in other climate variables), masking the multi-decadal temperature trend over a time scale shorter than 20 years with the effect that the longer term trend is not statistically detectable in the time series, if one chooses the time period only short enough.»

I'm very convinced that the physical process of global warming is continuing, which appears as a statistically significant increase of the global surface and tropospheric temperature anomaly over a time scale of about 20 years and longer and also as trends in other climate variables (e.g., global ocean heat content increase, Arctic and Antarctic ice decrease, mountain glacier decrease on average and others), and I don't see any scientific evidence according to which this trend has been broken, recently.

Recent work (e.g., Hurrell 1995, 1996; Thompson and Wallace 1998; Corti et al., 1999) has suggested that the observed warming over the last few decades may be manifest as a change in frequency of these naturally preferred patterns (Chapters 2 and 7) and there is now considerable interest in testing the ability of climate models to simulate such weather regimes (Chapter 8) and to see whether the greenhouse gas forced runs suggest shifts in the residence time or transitions between such regimes on long time - scales.

History unfolds over longer time scales, just like the climate.

Thus there are primarily internal system changes forcing climate responses, not primarily external such as the absolute value of solar power (except over much longer time scales).

«What we're going to be doing next is trying to understand more about the relationships between the proxies that we measured in the mosses, how they've changed over longer time scales, before the advent of the human influence on climate,» Dr. Amesbury revealed.

If a scientist and in particular climate scientists don't understand the wide swings that do occur in data over short multidecadal time scales then how can they be trusted with understanding the large climatic swings on longer millenia time scales or vise - versa.

It seems that every new climate scenario making the media over the past 20 years they always describe a warm future on a multidecadal scale ignoring a cool future as if variability didn't exist, but isn't scientific climatology primarily concerned with longer millenia time scales of a thousand years or more?

Weather changes on short time scales; climate over long ones.

It suggests that the ocean's natural variability and change is leading to variability and change with enhanced magnitudes over the continents, causing much of the longer - time - scale (decadal) global - scale continental climate variability.

The sensitivity he then derives is projected back using the 0.8 deg C warming over the 20th C. However, this is ludicrous — the sensitivity in the recent period can't be more than say, 1 ppmv per 0.1 deg C. Projected back you would have say a 10 ppmv (max) change over the 20th C. Paleo - climate constraints demonstrate that CC feedback even on really long time scales is not more than 100 ppmv / 6 deg C (i.e. 16 ppmv / deg C), and over shorter time periods (i.e. Frank et al, 2010) it is more like 10 ppmv / deg C. Salby's sensitivity appears to be 10 times too large.

The glacial - interglacial cycles are an example of tight coupling between climate and the carbon cycle over long time scales, but there is also clear evidence of the carbon cycle responding to short - term climatic anomalies such as the El Niño - Southern Oscillation (ENSO) and Arctic Oscillation (Rayner et al., 1999; Bousquet et al., 2000; C. Jones et al., 2001; Lintner, 2002; Russell and Wallace, 2004) and the climate perturbation arising from the Mt. Pinatubo volcanic eruption (Jones and Cox, 2001a; Lucht et al., 2002; Angert et al., 2004).

It is only over the longer time scales (decades) that the additional predictability that comes from external drivers of climate change (for instance, carbon dioxide, air pollution and ozone depletion) can start to be useful — but that's another post.

Gavin writes «Paleo - climate constraints demonstrate that CC feedback even on really long time scales is not more than 100 ppmv / 6 deg C (i.e. 16 ppmv / deg C), and over shorter time periods (i.e. Frank et al, 2010) it is more like 10 ppmv / deg C. Salby's sensitivity appears to be 10 times too large.»

You won't get * global * climate change over long time scales.

I still think your choice of the Chicxulub meteor is a difficult one to use as it so clearly had major and long lasting impacts over the time scales that current climate modellers are working on.

I have broad training in both atmospheric science and oceanography, and I am particularly interested in coupled atmosphere - ocean climate dynamics over long time scales.

The impact of land use change on the energy and water balance may be very significant for climate at regional scales over time periods of decades or longer.

Climate is individual weather observations / predictions integrated over time and area, taking longer - scale trends into account and allowing us to identify such trends.