Sentences with phrase «observed precipitation trends»

Zhang et al. (2007) showed that models using natural + anthropogenic forcings do a much better job of matching observed precipitation trends than either natural or anthropogenic alone.

Not exact matches

In terms of precipitation, a decrease was observed in annual precipitation over the period as a whole, although these trends «are not significant.»

«According to climate predictions, annual precipitation is likely to decrease in the Southwest but increase in the eastern United States during the 21st century, therefore, the observed diverse trends of surface water body areas since 1984 could continue to occur in the future,» said Xiao.

... A remarkable trend to decrease of precipitation is also observed for the central region of Chile, and the Argentinean Region of Cuyo, Province of Neuquén and the western part of Río Negro and Chubut.

There were no significant trends in mean annual total precipitation or total precipitation affected area but we did observe a significant increase in mean annual rain - free days, where the mean number of dry days increased by 1.31 days per decade and the global area affected by anomalously dry years significantly increased by 1.6 % per decade.

At the tail end of the full paper, capping a paragraph about a weak spot in the analysis — that the observed trend in extreme precipitation events exceeds what is produced by various climate models — comes a sentence about uncertainties:

(Top) Observed trends (% per decade) over the period 1951 to 2003 in the contribution to total annual precipitation from very wet days (i.e., corresponding to the 95th percentile and above).

Long - term trends in precipitation amounts from 1900 to 2005 have been observed in many large regions (Figure TS.9).

Observed U.S. trends in heavy precipitation (Kunkel et al. 2013)

For the entire Northern Hemisphere, there is evidence of an increase in both storm frequency and intensity during the cold season since 1950,1 with storm tracks having shifted slightly towards the poles.2, 3 Extremely heavy snowstorms increased in number during the last century in northern and eastern parts of the United States, but have been less frequent since 2000.11,15 Total seasonal snowfall has generally decreased in southern and some western areas, 16 increased in the northern Great Plains and Great Lakes region, 16,17 and not changed in other areas, such as the Sierra Nevada, although snow is melting earlier in the year and more precipitation is falling as rain versus snow.18 Very snowy winters have generally been decreasing in frequency in most regions over the last 10 to 20 years, although the Northeast has been seeing a normal number of such winters.19 Heavier - than - normal snowfalls recently observed in the Midwest and Northeast U.S. in some years, with little snow in other years, are consistent with indications of increased blocking (a large scale pressure pattern with little or no movement) of the wintertime circulation of the Northern Hemisphere.5 However, conclusions about trends in blocking have been found to depend on the method of analysis, 6 so the assessment and attribution of trends in blocking remains an active research area.

Van Haren et al (2012) also nicely illustrate the dependence of regional skill on lateral boundary conditions: simulations of (historic) precipitation trends for Europe failed to match the observed trends when lateral boundary conditions were provided from an ensemble of CMIP3 global climate model simulations, while a much better correspondence with observations was obtained when reanalyses were used as boundary condition.

Figure 3 shows Sahel precipitation trends from Held et al., expressed as July - September proportional amounts relative to the 1901 - 2000 observed mean.

Hoerling: «We can also say with high confidence that no appreciable trend toward either wetter or drier conditions has been observed for statewide average precipitation since 1895» — «At present, the scientific evidence does not support an argument that the drought there is appreciably linked to human - induced climate change... In short, the drought gripping California has been observed before.

1) Connection to global warming The model simulates an increase in Northern England precipitation in winter, but the trend is not as large as the observed one.

The model simulates an increase in Northern England precipitation in winter, but the trend is not as large as the observed one.

The widespread trend of increasing heavy downpours is expected to continue, with precipitation becoming less frequent but more intense.13, 14,15,16 The patterns of the projected changes of precipitation do not contain the spatial details that characterize observed precipitation, especially in mountainous terrain, because the projections are averages from multiple models and because the effective resolution of global climate models is roughly 100 - 200 miles.

Rigorous analyses have shown that natural variability alone can not explain the observed long - term trends of changing extremes in temperature and precipitation.12

Observed 1979 — 2008 trends in global surface temperatures, Z850 and low - latitude precipitation are shown in Fig. 9a, and the simulated trends in Z850 and precipitation from the GOGA and TOGA ensemble means are shown in Fig. 9b, c, respectively.

The model, forced with observed SSTs, generally reproduces the observed pattern of precipitation trends in the central and western tropical Pacific, with increases in convective precipitation of up to 0.8 mm / day / decade.

While Zhang et al. (2007) concluded globally that they had detected an anthropogenic influence on the overall latitudinal patterns of precipitation trends (that is, the climate model trends were of the same sign as the observed trends), in the latitude band that includes the majority of the United States population a mismatch between model projections and precipitation trends was found (Figure 1).

Pronounced long - term trends from 1900 to 2005 have been observed in precipitation amount in some places: significantly wetter in eastern North and South America, northern Europe and northern and central Asia, but drier in the Sahel, southern Africa, the Mediterranean and southern Asia.

... A remarkable trend to decrease of precipitation is also observed for the central region of Chile, and the Argentinean Region of Cuyo, Province of Neuquén and the western part of Río Negro and Chubut.

[10] Observed trends in precipitation and floods over Europe are in line with these future projections, however their climate change signal is quite complex.

On the other hand, a declining trend in precipitation has been observed in southern Chile, south - west Argentina, southern Peru and western Central America.