Open Access

Fig. 13

image

Download original image

Comparison of the new homogenised indices aa H, aa HN and aa HS, with the IHV index and the δ-corrected a NGK, a SOD and a ESK values. The left-hand plots show the time series and their respective best-fit linear regressions. The right-hand plots show scatter plots of the new indices against the test indices (a NGK/s(δ), a SOD/s(δ) or IHV) and the least-squares best-fit linear regression line. The linear correlation coefficient r is given in each case. Parts (a) and (b) are for aa HN and IHV; parts (c) and (d) are for aa HS and IHV; parts (e) and (f) are for aa HS and IHV; parts (g) and (h) are for aa H and the corrected a K values from Niemegk, a NGK/s(δ); parts (i) and (j) are for aa H and the δ-corrected a K values from Sodankylä, a NGK/s(δ), parts (k) and (l) are for aa H and the δ-corrected a K values from Eskdalemuir, a ESK/s(δ). For comparison, the bottom panel (parts m and n) compares the hemispheric homogenized indices aa HN and aa HS. In each panel, the grey area defines the estimated ±1σ uncertainty in aa H.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.