“though they cry out in my ears with a loud voice.” This seems cold of God, but actually it is not. God knows that when disaster strikes the people will not cry out to Him because they love Him and wish to repent of their sins, they will cry out to Him out of their selfish desire to save their lives and property.
“I will not listen to them.” God does not hear prayers simply because people pray. Everyone sins, but some people are prideful and unrepentant about their sin, and God will not listen to the prayers of wicked and unrepentant people; those prayers are an abomination to Him (Prov. 28:9). It is the prayer of a righteous person that accomplishes much (James 5:16). There are a number of verses that say God does not answer the prayers of the wicked (cp. Job 35:12-13; Prov. 15:29; Isa. 1:15; 59:1-2; Ezek. 8:17-18; Mic. 3:4; Zech. 7:12-13; and James 4:3). God spoke to Jeremiah, who was alive at the same time as Ezekiel, and told him on three different occasions not to pray for Judah (cp. Jer. 7:16; 11:14, 14:11; see commentary on Jer. 7:16).
[For more on God not hearing the prayers of the wicked or honoring their sacrifices, see commentary on Amos 5:22].