You can add the variable in browse.php
Add the variable in this section PHP Code:
// vars template
global $header, $footer, $category, $category_name, $category_description,
$link, $pagination, $category_path, $content, $editor,
$category_path_search_opt, $meta_keywords, $meta_description,
$page_title, $editors, $sponsored_link, $num_rows,
$num_rows_sponsored, $num_rows_premium;
and this section PHP Code:
DisplayTemplate($theme_path . "browse.html",
"\$header,\$footer,\$category_path,\$category_path_search_opt,".
"\$category,\$category_name,\$category_description,\$meta_keywords,".
"\$meta_description,\$page_title,\$editors,\$header,\$footer,\$num_rows,".
"\$pagination,\$cat,\$link,\$content,\$start_number,\$ma,\$editor,".
"\$sponsored_link,\$num_rows_sponsored,\$num_rows_premium");