Two questions arise related to this phenomenon described in the Gospels:

• Are these passages intending to say that this darkness covered the entire earth?
• Are these passages necessarily referring to an eclipse?

Neither proposition is at all certain. If I said (sitting in my house in Michigan), “Yesterday at noon there was darkness over the whole land,” would a person reading that assume I meant the entire earth? Or would they think that I meant all the land surrounding where I live (i.e., as far as I could see)? Surely they would assume the latter.

The Bible is no different. The notion that the entire earth was intended is not in the texts, which express things phenomenologically, as the Bible writers almost always do. Bible translations make it obvious that a local darkness was the authors’ intention. Out of 61 Bible translations I found for Mark 15:33, exactly four, or 7% (none of them among the most well-known translations) translated “the whole earth” or “all the earth.” Almost all the others used “land,” with a few rendering it “country” or “countryside.” I’m sure it would be similar for Matthew and Luke. If someone wants to find out, they can follow the link and type in those verses.

The King James Version does have “all the earth” at Luke 23:44, and 12 out of 61 translations (20%) have “earth” there. But as we can see, it is still a minority opinion among English Bible translators (16 out of 122 times, or 13% of the time). The word for “land” in all three Gospels is the same: gé (Strong’s Greek word no. 1093). It has a wide latitude of meanings in the Bible — “the earth, soil, land, region, country, inhabitants of a region.”

Kittel’s Theological Dictionary of the New Testament, a standard source, defines gé in its appearance in Mark 15:33 as “‘Land’ (in the geographical sense) ... (Palestine).” W.E. Vine’s Expository Dictionary of New Testament Words (under “Land”) states that at Luke 23:44 the word means “land as describing a country or region.” 

What about the interpretation of a solar eclipse? Very few Bible translations expressly state that, either. The only major ones I’ve found are Phillips and (unfortunately) the New American Bible. In the RSV, Matthew and Mark simply refer to “darkness” without indicating cause. Luke says “the sun’s light failed” but that can refer just as easily to a dust storm (which I shall defend) — or for that matter to a very severe thunderstorm — as to an eclipse. 

Catholics have no objection to astronomical calculations. If it is known that there could have been no solar eclipse at this place and time (and apparently that is the case, according to science), we accept that, and so seek another explanation of this darkness. An eclipse certainly can’t be “proven” from the text saying that the sun’s light failed. That being the case, we’re glad to learn of the scientific data that rules out an eclipse. That’s perfectly fine. It’s not the only option of interpretation. A solar eclipse has long been known to be impossible, anyway, because, as well-known commentator John Albert Broadus noted way back in 1886:

[T]he Passover was at the middle of the month, and the month always began with the new moon, so that the moon was now full, i.e., on the opposite side of the earth from the sun ... this was not an eclipse.

How plausible is a dust storm, then? It’s quite plausible, since it’s well-known that Israel has such storms every year — particularly in March and April, precisely at the time being discussed.  The Jerusalem Post reported on one such dust storm in Israel on March 2, 2014, which shut down an airport. A web page from rove.me noted “a probability of dust storms in spring” in Israel, and provided several photographs and a video of what they look like. Another web page about dust storms in Israel informed its readers:

‘Hamsin’ is an Arabic word. ... It refers to a unique set of weather conditions mostly in the spring and early summer months. In short a ‘hamsin’ is an oppressive, hot southerly or southeasterly, sandy wind blowing up from North Africa in the spring and summer months. There are approximately 50 days in a year when these weather conditions prevail in the Levant; North Africa and the Arabian Peninsula — hence the name. …

In Hebrew this weather condition is called a ‘sharav’ but in Israel it is commonly referred to by the Arabic name — hamsin. Typically, in Israel, during a Sharav, temperatures  can increase by 10° C within a few hours. This oppressive, dry heat is often accompanied by large amounts of dust.

In the 2013 book, The Impact of Desert Dust Across the Mediterranean, it is stated: “In a recent paper Ganor (1994) has presented a statistical analysis of the frequency of dust episodes (including dust storms) over central Israel. Most episodes occur in March or April ...” The book, Biogeochemistry of Trace Elements in Arid Environments (2007), by Fengxiang X. Han, noted that “Five to ten dust storms per year is a common occurrence in Israel.” On the same page is a photo of one such ominous storm, which looks like the famous Dust Bowl photos from the American west in the 1930s. The author refers to “three dust storms in the spring of 2001.” A 1963 book from the U.S. Navy described these annual Israeli dust storms as occurring during “April to May or early June” and noted that they “may reduce visibility to a few yards.”