Complex sentence: Frost weathering is most common in areas of high altitude, latitude and moisture, that is in alpine, periglacial, subpolar maritime and polar areas, in all these inviroments it acts alongside chemical and other types of physical weathering.
Split into simpler sentences: Frost weathering is most common in areas of high altitude, latitude and moisture, that is in alpine, periglacial, subpolar maritime and polar areas. In all these environments it acts alongside chemical and other types of physical weathering.