I’m aware of Dr Spencer and the arguments the denier crowd.
I’ve never found their arguments persuasive. About 15 years ago I didn’t have a firm opinion as to what the climate was actually doing so I investigated it myself. As I have a background that includes some classes in Heat and Mass Transfer as well as work experience using thermal analyses I approached the topic as I would dealing with any other thermal analysis. I found that mainstream climate science at a high level had done everything I would do to answer this question.
If you want to know if a system is warming or cooling you create an energy budget & measure the difference between the energy entering and leaving the system. We have satellites that measure the energy from the sun and the spectrum of light emitted by the Earth. They show a small but consistent imbalance of a few fractions of a watt/m^2 indicating slightly more energy is arriving than leaving the Earth.
If that’s true then using an energy budget we should be able to find parts of Earth warming based on where that energy can be transported to. Which is exactly what we find. As I’ve already mentioned we find an increase of 100’s of zettajoules in the oceans, melting ice, land and lower atmosphere. This evidence supports the warming Earth theory.
If the Earth is warming it’s either getting additional joules from somewhere or those joules are not leaving which again is something our energy budget can help with.
There are only three fundamental sources of heat the Earth experiences. Residual heat from its formation, radioactive decay from elements in Earths crust and energy from the sun. There’s been no widespread volcanism over the last century that can explain even in part the temperature increase. Radioactive decay is a consistent and decreasing process and cannot be cause of this measured increase.
That leaves the sun. As I’ve already mentioned the sun has actually been quiet and it’s output slightly down for the last decade or more. So it’s not from an increase in the suns output
That leaves us with the Earth retaining more of the energy it does receive. The only way for energy to leave the Earth is via radiative transfer. Which means we should find something reducing the amount of energy leaving the planet.
As I’ve already mentioned we’ve known about the greenhouse effect of certain gases for over 100 years and we can see it’s effect in the measured spectrum the Earth radiates.
“Figure 6: Radiation transmitted and absorbed by the cloud-free atmosphere. The left part of the figure shows the solar radiation and the right part shows Earth’s radiation. The blackbody curve at 5525 K (red curve in the top panel) represents the incident (downgoing) solar radiation at the top-of-the-atmosphere. The red filled area is the radiation transmitted through the atmosphere. The difference between the two (the white area between the red curve and the red area) is the amount absorbed by the atmosphere. For Earth’s radiation blackbody curves are shown for three temperatures (210, 260, and 310 K) and represent upgoing radiation from the surface. This is a key figure. From
commons.wikimedia.org”
Being from Houston it shouldn’t surprise you but the markets do track every barrel of oil sold and for what purpose. We also understand the chemistry behind what we do with our fossil fuels so we know what kinds and how much of each type of exhaust gases we should expect to see in the atmosphere. When we measure the amount of CO2, methane and other industrial exhaust gases we see what we would expect - increasing amounts. Once more the isotope ratio of carbon in the atmosphere show the bulk is from old carbon which is what one should expect from burning fossil fuels and not from a natural source.
Direct experimental studies confirm atmospheric CO2 increasing the energy imbalance over the course of several years
Scientists have observed an increase in carbon dioxide’s greenhouse effect at the Earth’s surface for the first time. The researchers, led by Berkeley Lab scientists, measured atmospheric carbon dioxide’s increasing capacity to absorb thermal radiation emitted from the Earth’s surface over an...
newscenter.lbl.gov
Finally, our understanding of what’s happening now shows what’s different from previous glacial / inter-glacial periods. In previous warm periods periodic changes in the orbital mechanics of Earth (Milankovitch Cycles) begin increasing the amount of sunlight absorbed, which begins melting ice which changes the albedo providing a feedback for more warming. Warming permafrost and oceans release more CO2 and other greenhouse gases further providing warming feedback.
Today CO2 led the increase in temperatures instead of lagged it. The rate of change in temperature is about 10 times faster than previous post ice-age recoveries.
So the case is pretty open and shut confirmed by multiple avenues of investigation. The Earth is warming, it’s caused by greenhouse gases, it’s not natural and it’s caused by us.
Until the denier camp can put forth a hypothesis that takes all of this evidence into account in accordance with known laws of physics better than the current theory they aren’t going to convince me of anything and it shouldn’t convince you.