合并2D php数组的元素

I have one 2d PHP array that looks like this.

Array
(
    [0] => Array
        (
            [year] => 1990
            [Hydro] => 17071.0288392
            [Coal] => 
        )
    [1] => Array
        (
            [year] => 2000
            [Hydro] => 6708.00288392
            [Coal] =>
        )
    [2] => Array
        (
            [year] => 1990
            [Hydro] => 
            [Coal] => 17071.0288392
        )
    [3] => Array
        (
            [year] => 2000
            [Hydro] => 
            [Coal] => 2100.0288392
        )
)

Is there a way to merge elements together depending on value of year key so I would get something like this expected result

Array
(
    [0] => Array
        (
            [year] => 1990
            [Hydro] => 17071.0288392
            [Coal] => 17071.0288392
        )

    [1] => Array
        (
            [year] => 2000
            [Hydro] => 6708.00288392
            [Coal] => 2100.0288392
        )

)

Thank you a lot!

<?php

   $arrNew = array();

   foreach ($arrCurr as $arr) {
     $arrTemp = array();

     for ($i=1; $i < count($arr); $i++) {
       $arrTemp[] = $arr[$i];
     }

     $arrNew[$arr['year']][] = $arrTemp;

   }

   print_r($arrNew);

?>