Trigger a function during onload

Enqueue your script only when the page you want it on is requested:

function wpa_script() {
    if( is_page( 'global-network' ) ){
        wp_enqueue_script(
            'wpa_script',
            get_template_directory_uri() . '/js/my_worldmap.js',
            array('jquery')
        );
    }
}
add_action( 'wp_enqueue_scripts', 'wpa_script' );

See is_page() in Codex.