I know all of our cats love to lie in the garden all day if it's sunny and who can blame them?
Cats who have pale ears and noses are at risk from getting sunburn just as we are; they can even get skin cancer.
To help prevent this try and keep your cats in during the hottest hours of the day (11am – 2pm), if this is not possible you can put sunscreen on their ears and noses.
Ask your vet which type of sunscreen is safe to put on your cat. You need to obtain a non-toxic brand or buy a specialist brand just for pets, since your cat is likely to lick some of it off. Using it is very straightforward, just apply to the ears and nose a few times a day.