The timestamp for the system is set to Greenwich Mean Time.Since we are a global organization, that just makes sense. If you want to change it to your local timezone you are able to do that yourself on your profile page:
Go to your profile by clicking on your name in the upper right corner while logged in.
Click on the option to Edit Profile.
(You may need to click on EXPAND ALL if you do not see all the choices)
Just above the big description box is a dropdown for selecting timezone. Just set the timezone by clicking on the dropdown.
I hope that helps.