The weather forecast in a certain place on January 22, 2013 is -4°C to 5°C. What is the local temperature difference (the difference between the highest temperature and the lowest temperature) on this day?
某地2013年1月22日的天气预报是-4℃～5℃，这一天当地的温差(最高气温与最低气温的差)是多少℃
<gadget id="calculator">5 - (-4)</gadget>
<output>9</output>

<result>9</result>