Ubuntu上Hexo安装问题

Ubuntu上安装了nodejs和各种依赖后，输入npm install -g hexo-cli遇到以下问题
懂得帮帮忙，悬赏！

 npm WARN optional Skipping failed optional dependency /hexo-cli/chokidar/fsevents:
npm WARN notsup Not compatible with your operating system or architecture: fsevents@1.1.2
npm ERR! Linux 4.8.0-36-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "install" "-g" "hexo-cli"
npm ERR! node v4.2.6
npm ERR! npm  v3.5.2
npm ERR! path /usr/local/lib
npm ERR! code EACCES
npm ERR! errno -13
npm ERR! syscall access

npm ERR! Error: EACCES: permission denied, access '/usr/local/lib'
npm ERR!     at Error (native)
npm ERR!  { [Error: EACCES: permission denied, access '/usr/local/lib']
npm ERR!   errno: -13,
npm ERR!   code: 'EACCES',
npm ERR!   syscall: 'access',
npm ERR!   path: '/usr/local/lib' }
npm ERR! 
npm ERR! Please try running this command again as root/Administrator.

npm ERR! Please include the following file with any support request:
npm ERR!     /home/huixiong/npm-debug.log

sudo npm install -g hexo-cli