The warm colours feel much heavier. When they are down, the composition feels stable and static. The top is more airy.
In both the reds are just coming forward, creating the impression of space.
Contrast of temperature can also be used to create mood. Though reactions to colours are somewhat subjective and different from culture to culture, general tendencies apply. Arrangements dominated by cool colours typically evoke feelings of peace, quiet, serenity, and tranquility. Warm arrangements often bring about feelings that are relatively active and dynamic, from vivacity and joy to anger.