The most common and most likely answer to this crossword clue is the 3 plus 5 letter word SEA LEVEL
I've seen this crossword clue in The Times
S
E
A
L
E
V
E
L
More clues leading to the result SEA LEVEL
- A lake confined by raised banks that should be higher than this
- Aquatic creature almost always next to lake causes rising concern
- Rise in this? Flood barriers up to protect nearly everything
- Of average height, in the main
- Directions on youngster’s examination from which height is determined
- Mainly horizontal height!
Buddy explains!
The straight part
We know that "that should be higher than this" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case that should be higher than this = sea level.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.