All Figures

$\begin{figure} \par\includegraphics[width=12.1cm,clip]{H4300F1.EPS} \end{figure}$ Figure 1: Coaligned context SOHO/MDI (left panel; B_||) and TRACE (right panel; 1600 Å) images from JOP72 data-cubes of February 26, 1999. These images represent of the averages of one hour of time-series, 60 and 240 frames respectively.
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In the text

$\begin{figure} \par\includegraphics[width=11.8cm,clip]{H4300F2.EPS} \end{figure}$ Figure 2: In panel A we show the spatial variation in the altitudes at which the plasma- $\beta$ is of order unity in the TRACE field of view, the $\beta$ TH. We have included solid contours for reference and each is separated by 0.25 Mm. panels B through D show one example of the integrated oscillatory power in the 3-8 mHz band of the 1700, 1600 and 1550 Å TRACE UV bandpasses respectively. On each panel we have overplotted the contours of panel A. Note the clear correlation between the reduced power and the contours.
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In the text

$\begin{figure} \par\includegraphics[width=12.5cm,clip]{H4300F3.EPS} \end{figure}$ Figure 3: The two-dimensional histograms of TRACE oscillatory power and $\beta$ TH derived from panels B through D of Fig. 1. The colour scale in each panel indicates the number of image pixels with that particular combination of oscillatory power and $\beta$ TH. We see that, in each panel, there are two distinct correlations present, the "tail'' to the lower-left indicating the correlation of low oscillatory power and low $\beta$ TH and the broad power correlation of the "canopy'' at a $\beta$ TH of around 1.75 Mm.
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In the text

$\begin{figure} \par\includegraphics[width=11.8cm,clip]{H4300F4.EPS} \end{figure}$ Figure 4: In panel A we show the spatial variation in the altitudes at which the plasma- $\beta$ is of order unity in the SOHO/MDI field of view, the $\beta$ TH. We have included solid contours for reference and each is separated by 0.25 Mm. panels B through D show one example of the integrated oscillatory power in the 3-8 mHz band of the B_||, V_|| and continuum intensity (I) MDI filtergrams respectively. These filtergrams are formed significantly lower in the atmosphere than those of Fig. 2 ( $\sim$ 0.2 Mm). On each panel we have overplotted the contours of panel A. Careful inspection of panel D shows that the only significant drops in oscillatory power occur in the very darkest, deepest, regions of the $\beta$ TH.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4300F5.EPS} \end{figure}$ Figure 5: Sample linear fit of the phase-difference gradient, $M_{\Delta \phi }$ , between 3 and 8 mHz at position coordinates [-170, 35] and a $5\hbox {$^{\prime \prime }$ }\times 5\hbox {$^{\prime \prime }$ }$ region around that point for the 1700-1600 Å bandpass pair. The dots mark the positions, in ( $\Delta \phi _{ij}$ , $\nu$ ) space, of every point in the spatially degraded cube (we also show the variation of mean and mean plus/minus 1- $\sigma$ of $\Delta \phi _{ij}$ at each $\nu$ -indicated by the dash-dot and solid lines respectively). Of these points, about 10% lie between 3 and 8 mHz with a net cross-power greater than, or equal to, ten. This latter set are indicated by triangles and their size indicates the net cross-power, the quantity used to weight the linear fit. The solid line indicates the fit to the triangles and has a gradient of $7.4\pm 0.8$ $\hbox{$^\circ$ }\;{\rm mHz^{-1}}$ .
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In the text

$\begin{figure} \par\includegraphics[width=13cm,clip]{H4300F6.EPS} \end{figure}$ Figure 6: As in Fig. 2, in panel A, we show the model-derived altitudes at which the plasma- $\beta$ is of order unity in the TRACE field of view. In panels B through D we show the fitted phase-difference gradient ( $M_{\Delta \phi }$ ) maps as discussed in the text. Again, we note more than a passing correspondence between the overplotted contours and the darker regions of the $M_{\Delta \phi }$ maps.
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In the text

$\begin{figure} \par\includegraphics[width=12.54cm,clip]{H4300F7.EPS} \end{figure}$ Figure 7: The two-dimensional histograms of phase-difference gradient ( $M_{\Delta \phi }$ ) and $\beta$ TH derived from panels B through D of Fig. 6. The colour scale in each panel indicates the number of image pixels with that particular combination of $M_{\Delta \phi }$ and $\beta$ TH. As for Fig. 3, we see that, in each panel, there are two distinct correlations present. The "tail'' to the lower-left indicating the correlation of low $M_{\Delta \phi }$ and low $\beta$ TH and the broader $M_{\Delta \phi }$ correlation of the "canopy'' at a $\beta$ TH of around 1.75 Mm. In this case, the "resolution'' of the histograms are degraded compared to those of Fig. 3 but this is due to the spatial degradation necessary to compute $M_{\Delta \phi }$ from the full resolution TRACE image.
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In the text

$\begin{figure} \par\includegraphics[width=12.1cm,clip]{H4300F1.EPS} \end{figure}$	Figure 1: Coaligned context SOHO/MDI (left panel; B_\|\|) and TRACE (right panel; 1600 Å) images from JOP72 data-cubes of February 26, 1999. These images represent of the averages of one hour of time-series, 60 and 240 frames respectively.
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