Depending on where you live you will learn to dive or do most of your diving in either cold or warm water. For example in the UK all diving is considered to be cold water scuba diving - sometimes very cold indeed! On the other hand, diving in the Caribbean is considered to be warm water diving for just about the whole year.
If you learn to dive in warm water you are fortunate enough to be able to learn in comfortable conditions. Your scuba diving equipment will be fairly simple, consisting of a light wet suit and basic scuba gear. However cold water diving involves using a dry suit in order to keep warm. This is a bulky item and introduces additional buoyancy considerations. Configuring your air hoses and positioning your equipment becomes more important and learning to adjust your gear or practice exercises with thick neoprene gloves can take some getting used to.
Dry suit diving needs additional training. The dry suit is a buoyancy device in the same way as your buoyancy jacket and needs to be controlled appropriately so that you do not find yourself torpedoing uncontrollably to the surface because you failed to dump a little air at the correct time. The dry suit and bulky warm undersuit will mean that you must carry much more weights to achieve neutral buoyancy than you would need if diving in warm water in a thin wetsuit.
Another difference with cold water is that it is often darker and therefore a good torch is also needed more often than not compared to warm water diving. Also, being cold reactions and responses to occurrences can be slower or less controlled than when you are comfortably warm. This can have safety considerations and is a good reason for the extra training that is usually expected for qualifying a cold water diver.
One good thing about learning to dive in colder water conditions is that experience shows that this route makes for a better and safer diver. The extra training and harsher conditions prepare a scuba diver for more eventualities and create a more resilient and adaptable diver. The other good thing is that a cold water diver always has the fantastic thought of a warm water diving holiday to look forward to. I am sure that the reverse cannot be true for the otherwise more fortunate warm water diver!
