Are people who live in extremely hot regions obliged to fast even though it is difficult for them?

In the Sahara region, the month of Ramadan may come in the summer and
it is difficult for them to fast and it may be impossible for them.
This will continue for a number of years. How should these people
fast?.
Praise be to Allaah.
When the month of Ramadan begins, every Muslim who is accountable, not
travelling and in good health is obliged to fast. Allah says
(interpretation of the meaning):
"So whoever of you sights(the crescent on the first night of) the
month (of Ramadan i.e. is present at his home), he must observe Sawm
(fasts) thatmonth, and whoever is ill or on a journey, the same number
[of days which one did not observe Sawm (fasts) must be made up] from
other days"
[al-Baqarah 2:185].
So fasting is obligatory even at times when it is hot, because fasting
Ramadan is one of the pillars of Islam. If a personfasts and then
suffers intense thirst in which there is the fear that he may die, he
may break the fast by drinking enough to keep him alive,then he should
refrain from eating and drinking, and make up that day at another
time. And Allah knows best.
And Allah is the source of strength. May Allah send blessings and
peace upon our Prophet Muhammad and his family and Companions. End
quote.
Standing Committee for Academic Research and Issuing Fatwas
Shaykh 'Abd al-'Azeez ibn 'Abd-Allaah ibn Baaz, Shaykh 'Abd-Allaah ibn
Ghadyaan, Shaykh Saalih al-Fawzaan, Shaykh 'Abd al-'Azeez Aal
al-Shaykh, Shaykh Bakr Abu Zayd
Fataawa al-Lajnah al-Daa'imah – vol. 2, 9/145.