Ocean heat content and vertically averaged temperature data for the oceans have been the subjects of a couple of recent blog posts. As one might expect, the discussions on those threads tend to shift to the subject of whether or not the infrared (longwave) radiation from manmade greenhouse gases can cause any measureable ocean warming at the surface or at depth. According to the hypothesis of human-induced global warming, the warming of the global oceans to depth and the related ocean heat uptake are a function of the radiative imbalance caused by manmade greenhouse gases. There are a number of arguments for and against the hypothetical anthropogenic warming of the oceans.
So the topic of this post is ocean warming. I’ll present different opinions/arguments on anthropogenic ocean warming.
For a detailed overview of ocean heat content data, please see the post Is Ocean Heat Content Data All It’s Stacked Up to Be? And see the post AMAZING: The IPCC May Have Provided Realistic Presentations of Ocean Heat Content Source Data for another discussion by the IPCC.
INFRARED RADIATION CAN ONLY PENETRATE THE TOP FEW MILLIMETERS OF THE OCEAN SURFACE AND THAT’S WHERE EVAPORATION TAKES PLACE
It is often argued that infrared radiation from manmade greenhouse gases can only penetrate the top few millimeters of the ocean surface and that’s where evaporation occurs. That argument then continues that additional infrared radiation from anthropogenic greenhouse gases can only add to surface evaporation, and cannot heat the oceans. On the other hand, sunlight reaches into the oceans to depths of 100 meters or so, though most of it is absorbed in the top 10 meters. Even so, sunlight’s ability to warm the oceans is many orders of magnitude greater than infrared radiation. One of my earliest memories of this argument came from Robert E. Stevenson’s (Oceanographer Scripps) 2000 article Yes, the Ocean Has Warmed; No, It’s Not ‘Global Warming’. In April of this year, looking for solid answers on this topic, Roy Spencer presented the same arguments and a few counter arguments in his post, Can Infrared Radiation Warm a Water Body?
Field tests reported in the 2006 post Why greenhouse gases warm the oceans at RealClimate are often cited by those who believe infrared radiation is responsible for ocean warming. That guest post by Peter Minnett of the University of Miami includes:
the rest
Arguments For and Against Human-Induced Ocean Warming | Watts Up With That?
So the topic of this post is ocean warming. I’ll present different opinions/arguments on anthropogenic ocean warming.
For a detailed overview of ocean heat content data, please see the post Is Ocean Heat Content Data All It’s Stacked Up to Be? And see the post AMAZING: The IPCC May Have Provided Realistic Presentations of Ocean Heat Content Source Data for another discussion by the IPCC.
INFRARED RADIATION CAN ONLY PENETRATE THE TOP FEW MILLIMETERS OF THE OCEAN SURFACE AND THAT’S WHERE EVAPORATION TAKES PLACE
It is often argued that infrared radiation from manmade greenhouse gases can only penetrate the top few millimeters of the ocean surface and that’s where evaporation occurs. That argument then continues that additional infrared radiation from anthropogenic greenhouse gases can only add to surface evaporation, and cannot heat the oceans. On the other hand, sunlight reaches into the oceans to depths of 100 meters or so, though most of it is absorbed in the top 10 meters. Even so, sunlight’s ability to warm the oceans is many orders of magnitude greater than infrared radiation. One of my earliest memories of this argument came from Robert E. Stevenson’s (Oceanographer Scripps) 2000 article Yes, the Ocean Has Warmed; No, It’s Not ‘Global Warming’. In April of this year, looking for solid answers on this topic, Roy Spencer presented the same arguments and a few counter arguments in his post, Can Infrared Radiation Warm a Water Body?
Field tests reported in the 2006 post Why greenhouse gases warm the oceans at RealClimate are often cited by those who believe infrared radiation is responsible for ocean warming. That guest post by Peter Minnett of the University of Miami includes:
However, some have insisted that there is a paradox here – how can a forcing driven by longwave absorption and emission impact the ocean below since the infrared radiation does not penetrate more than a few micrometers into the ocean?
So this argument was considered by climate scientists. The post then goes on to describe why it’s not an inconsistency and then to present the results of field tests. My Figure 1 is Figure 2 from that RealClimate post.
the rest
Arguments For and Against Human-Induced Ocean Warming | Watts Up With That?