framework: PHP Notice: date_default_timezone_set(): Timezone ID '' is invalid

[Mon Mar 23 02:31:33.059828 2015] [:error] [pid 3372:tid 139994861631232] [client 172.16.10.180:58471] PHP Notice:  date_default_timezone_set(): Timezone ID '' is invalid in /export/htdocs/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/LoadConfiguration.php on line 41
[Mon Mar 23 02:31:35.617828 2015] [:error] [pid 3372:tid 139994861631232] [client 172.16.10.180:58471] PHP Fatal error:  Uncaught exception 'ErrorException' with message 'date_default_timezone_get(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone.' in /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php:248\nStack trace:\n#0 [internal function]: Illuminate\\Foundation\\Bootstrap\\HandleExceptions->handleError(2, 'date_default_ti...', '/export/gw.molp...', 248, Array)\n#1 /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php(248): date_default_timezone_get()\n#2 /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php(543): Monolog\\Logger->addRecord(400, 'exception 'Erro...', Array)\n#3 /export/htdocs/vendor/laravel/framework/src/Illuminate/Foundation/Exceptions/Han in /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php on line 248
[Mon Mar 23 02:31:36.783063 2015] [:error] [pid 3372:tid 139994861631232] [client 172.16.10.180:58471] PHP Fatal error:  Uncaught exception 'ErrorException' with message 'date_default_timezone_get(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone.' in /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php:248\nStack trace:\n#0 [internal function]: Illuminate\\Foundation\\Bootstrap\\HandleExceptions->handleError(2, 'date_default_ti...', '/export/gw.molp...', 248, Array)\n#1 /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php(248): date_default_timezone_get()\n#2 /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php(543): Monolog\\Logger->addRecord(400, 'exception 'Symf...', Array)\n#3 /export/htdocs/vendor/laravel/framework/src/Illuminate/Foundation/Exceptions/Han in /export/htdocs/vendor/monolog/monolog/src/Monolog/Logger.php on line 248

• laravel/framework (v5.0.18)

@taylorotwell i am getting this error, please rectify.