Link: https://grist.org/cities/urban-trees-arent-just-nice-scientists-say-theyre-mandatory/

How many lives would have been saved if European cities had taken urban forestry seriously over the past few decades?

It can be an easy thing to test yourself, depending on local geography. Go for a walk in a forested area, even lightly, and then walk in an open field, then walk on a street. The temperature difference is easy to notice.

There's a trail nearby that goes from lightly forested to pavement next to a road, and then back to lightly forested. There's easily a 5-10*c difference when on the pavement, it's like hitting a wall of heat.

Edit: this is to say: there should be no doubt about the effectiveness and necessity of urban tree cover. Green walls/roofs, light coloured roofs, green covered parking lots, etc. Solar panels also work well to block the sun, and provide extra power as well.

Trees are by far the best at cooling but yes in situations where they won't fit the other options should be considered.