Summary: The claim is misrepresenting real scientific work.
I skimmed 13 articles taken from the list of 400. Of those 13,
2 were probably never peer reviewed and should not be considered scientific.
9 were building up the theory of climate change. These frequently criticized other climate models in small ways.
1 was a survey about attitudes and opinions.
1 made credible criticisms of mainstream climate science, presenting an alternative model that suggests human contributions to CO2 increases and global warming are real, but smaller than indicated by other models
To answer your question I skimmed a semi-random sample of papers from the link titled Skeptic Papers 2017 (1). I selected 12 papers by scrolling down the page, stopping at a random place, and selecting whatever was at the top of my window. This is not a robust random sample, but it will have to do. My sample is also not huge, but is hopefully large enough to give me a flavor of what these collected papers say.
I have documented all of the papers I skimmed without leaving any out, and recorded them in this google spreadsheet.
When I was skimming the papers I was trying to answer three questions.
Does the paper explicitly criticize current prevailing science on Anthropogenic Climate Change?
If #1 is a no, does it present evidence that contradicts fundamental pieces of the science of Anthropogenic Climate Change? The page that listed all of these sources has copy pasted quotes from the scientific papers that presumably show the part of the scientific paper that "casts doubt" on anthropogenic climate change. I would go and find the quote in its original context see if it actually attacks mainstream climate change science. To answer this question I have to rely on my own limited understanding of climate science. I am not an expert climate scientist.
Is the scientific paper published in a reputable (non-predatory) journal? To answer this I looked at who owns the journal; the major publishing houses provide quality control for their journal's peer review processes. I also looked at the journal's impact metrics; junk journals tend to score very low on these metrics.
By contrast, all of the other publications had professional websites, had been operating for a long time, and have clear citation statistics (measurements of scientific impact).
Question 1: Explicit criticism of mainstream climate science. Other than the two papers discussed above, only one other paper, Harde 2017, explicitly criticizes mainstream climate science in the abstract, conclusions, or other parts that I skimmed. There may be other explicit criticisms that were buried in the body of the paper. Harde thinks that CO2 will leave the atmosphere quicker than the IPCC estimates.
This one paper levels a substantive criticism at mainstream climate science.
Question 2: Does the paper contradict fundamental pieces of climate science?
Do the 9 remaining papers present fundamental contradictions to mainstream climate science?
For example Lachniet et al. used data from "fast-growing stalagmites" to study monsoon cycles in Central America. Because their data is from between 1900 and 30 years ago, only one of their data points can actually be used to look at modern climate change. One of their conclusions is that other people who have made climate models of Central American rainfall are improperly leaving out the effects of the El-Nino cycle. They explicitly say that "long-lived greenhouse gas concentrations in the atmosphere" affect the El-nino cycle, which itself has a large impact on rainfall. Nothing this paper says really casts doubt on the broad conclusions of climate science.
3 papers looked at the effect of solar forcing on climate. Solar forcing refers to the changes in climate due to fluctuations in how much light Earth gets from the sun. (Li et al.,Yndestad and Solheim, 2017,Li et al) Solar forcing is fairly well known, and precisely modeling it will allow climate scientists to better model climate overall. Once again, these papers are building up the scientific understanding of the specifics of climate, not tearing it down. (Some of these papers are also about climate from thousands of years ago.)
Stenhouse et al. surveyed American Meteorological Society members about their views on climate change. 63% said that climate was either half or mostly caused by humans. The main conclusion of this paper was that many climate scientists are sick of all of the arguing. This paper isn't really evidence for or against climate change. Climate doesn't care about our opinions and beliefs.
While skimming through these papers I do see a normal level of skepticism and doubt. The scientists criticize other scientists models. Saying they are too conservative, or underestimate the impact of variable X on variable Y. Nowhere do I see them trying to say that climate change science is all wrong.
After I wrote the above answer, Snopes published a review of a Breitbart article which was based on the above post. Snopes came to largely the same conclusions, and were able to get quotes from some of the actual scientists whose papers were being misrepresented. These scientists believe that their work is being misrepresented by these bloggers.
I do not agree with Breitbart's assessment of my work. My paper does not discuss 20th century anthropogenic warming trends, but decadal to centennial variability in the monsoon precipitation of the southern Tibetan Plateau.
Our paper certainly does not say that “global warming is a myth”... Our main results showed that the models appear to be too conservative and simulate Arctic sea ice that is not sensitive enough to changes in global temperatures.