2013 Blue is a free theme for WordPress created by Joen A..
Blue color scheme for Twenty Thirteen.
(Description "2013 Blue" Theme from wordpress.org)
You can download 2013 Blue for free via the provided download link and include it into your themes folder of your WordPress installation. Also you can directly search for it in the WordPress admin interface in the themes section and install and activate it from there.
More information, screenshots and reviews of 2013 Blue Theme can be found here.