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' Circles in Europe represent 1 to 7,500 data series.

Figure 1.8. Locations of significant changes in observations of physical systems (snow, ice and frozen ground; hydrology; coastal processes) and biological systems (terrestrial, marine and freshwater biological systems), are shown together with surface air temperature changes over the period 1970 to 2004 (from the GHCN-ERSST datatset). The data series met the following criteria: (1) ending in 1990 or later; (2) spanning a period of at least 20 years; (3) showing a significant change in either direction, as assessed by individual studies. White areas do not contain sufficient observational climate data to estimate a temperature trend.

Table 1.12. Global comparison of significant observed changes in physical and biological systems with regional temperature changes. Fraction of 5°x5° cells with significant observed changes in systems (from studies considered in this chapter) and temperature changes (for 1970 to 2004 from the GHCN-ERSST dataset (Smith and Reynolds, 2005)) in different categories (significant warming, warming, cooling, significant cooling). Expected values shown in parentheses are for the null hypotheses:

(i) significant observed changes in systems are equally likely in each direction,

(ii) temperature trends are due to natural climate variations and are normally distributed,

(iii) there is no relationship between significant changes in systems and co-located warming.

Table 1.12. Global comparison of significant observed changes in physical and biological systems with regional temperature changes. Fraction of 5°x5° cells with significant observed changes in systems (from studies considered in this chapter) and temperature changes (for 1970 to 2004 from the GHCN-ERSST dataset (Smith and Reynolds, 2005)) in different categories (significant warming, warming, cooling, significant cooling). Expected values shown in parentheses are for the null hypotheses:

(i) significant observed changes in systems are equally likely in each direction,

(ii) temperature trends are due to natural climate variations and are normally distributed,

(iii) there is no relationship between significant changes in systems and co-located warming.

Temperature cells

Cells with significant observed change consistent with warming

Cells with significant observed change not consistent with warming

Significant warming

50% (2.5%)

7% (2.5%)

Warming

34% (22.5%)

6% (22.5%)

Cooling

3% (22.5%)

0% (22.5%)

Significant cooling

0% (2.5%)

0% (2.5%)

Chi-squared value (significance level)

0 0

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