What is your View on Global warming?
Your question is simply too complex and complicated to answer in a sentence .. or even a paragraph. But .. to crunch it to the barest minimum:
(1) Is the Earth's average global temperature warmer today then it was in the late 1800s/early 1900s?
Very probably, almost a certainty. But it is NOT warmer everywhere .. in fact, much of the southeastern U.S. (including at least parts of LA) is actually cooler now than it was in the 1930s & 1940s, although there has been a upward run of temps since the 1970s.
(2) Is human activity contributing to this apparent warming?
Very probably, almost a certainty. BUT - it is not just about Carbon Dioxide (CO2) .. for example, land-use changes add to the problem.
(3) Is ALL of the current/recent warming due to human activities, or is Mother Nature a player here?
I think Nature is a major player, and 'her' contributions are extremely hard to ferret out of the whole process. There are simply so many internal system feedbacks and responses that it must be extremely difficult to attribute one effect or another as entirely "human" or entirely "natural." And this is the REAL debate in my mind: how much warming (climate change) is "natural" and how much is a function of human activities. I do not believe that we are ready (capable) to answer that.
(4) Is the current warming an Earth all-time record?
Possibly, but I do not believe that our technology to estimate historical temperatures can accurately answer that question. Remember, the first truly reliable thermometers weren't invented until the 1700s, and were probably not routinely used for another 100 years or more after that! So when you see temperature records dating back before the mid-1800s, these are driven largely by data like tree-rings and ice cores. This is data that I would label as "fuzzy," as in not entirely reliable. Plus .. I can show you a number of issues that compromise the temperature records since the late 1800s .. issues that make your head spin!!
(5) Do we know about "natural" periods of climate change?
Well, of course there are the Ice Ages ... but in a shorter window of time, there continues to be some pretty impressive evidence of the "Medieval Warm Period" (roughly 900s-1200s?), and any warming then was NOT a function of human activity nor the "infernal combustion engine" and fossil fuels. And then there is the "Little Ice Age" (roughly 1600s-1800s) ... another "natural" climate "shift," but in the other direction!
By the way, over the last million years, the "warm" periods of Earth history between the Ice Ages are the "short" periods .. Ice ages last something like 100,000 years .. the "warm" periods only last 10-15,000 years (all are very round numbers!) .. and our current "warm" spell is about 12,000 years old! That's why in the 1960s and 1970s, many climatologists were warning of an impending return to another Ice Age. Now, some warming experts suggest that the current warming trend will be so dramatic as to offset and disrupt the natural "ice age cycle."
I could go on for PAGES, so let's close with this ...
(6) Is global warming/climate change something to be concerned about?
Yes ... but let's allow the climate-science specialists to continue an "open" debate of the issue in the science arena, not the political arena. Contrary to what you may read, there are more than "just a handful of nay-sayers." And, not all of the "contrarians" are funded by the oil-&-gas industry - in fact, in my experience, most are not funded. Instead, they analytically and critically (science critique) assess the data and the models used to make the warming projections and scenarios.
And ... closer to home ... I have argued for a long time (most recently at an EPA-sponsored roundtable discussion) that even if "global warming" is entirely natural -- or, regardless of the cause - Louisiana is quite possibly the state with the MOST at risk. Even very modest sea-level rise is further exacerbated by our subsiding coast, giving coastal Louisiana one of the higher "apparent" sea-level rise rates on the planet.
And sinking marshes and coastal zone also mean (1) greater weather/Gulf threats to coastal communities, (2) lost resources for the Gulf fisheries (some suggest that upwards of 40% of the productivity in the Gulf has a direct link to the central Gulf Coast marshes), and (3) ever increasing threats to our oil-and-gas industry. And (3) is possibly the most important of all .. not just for Louisiana, but for the entire nation, since upwards of 25% of U.S. oil and natural gas comes through Louisiana.
A VERY incomplete answer .. but a start. Hope this gives you some food for thought!