If the minimum temperature in a city is -1°C and the maximum temperature is 2°C on February 1, 2006, what is the maximum temperature difference on this day?
某市2006年2月1日的最低气温为-1℃，最高气温为2℃，则这一天的温差最大是多少℃．
<gadget id="calculator">2 - (-1)</gadget>
<output>3</output>

<result>3</result>