When diving, depending on the diving site, there are different probabilities of encountering sea currents.
As the name suggests, the descending current is the downward ocean current, which can be seen from the bubbles exhaled from the three people's mouths. The bubbles that were originally rising suddenly scattered around them in a ring shape, and then began to float downward. The two turtles not far away retreated into the crevice of the rock seeing that the situation was not good. At the same time, the vision of the three of them began to become cloudy.
Fortunately, except for Zhang Heng, the other two are not newbies, including Han Lu, it is not the first time they have encountered ocean currents, so they will not be as flustered as beginners. His body stuck to the stone wall, grabbing the stone wall like a gecko.
On the other hand, Nelly turned on the flashlight she carried with her, took a photo of the big rock closest to Zhang Heng, and signaled Zhang Heng to go over, and she also swam there. The speed of their descent was not fast, which indicated that they met The current was not too strong, which made Nelly relieved, and Han Lu and Zhang Heng were also very calm.
The most dangerous thing underwater is to fall into a panic, not only can't solve any problems, but the random struggle will accelerate the consumption of oxygen, and the wrong operation is likely to bring more trouble, because Han Lu has enough diving In experience, Nelly is not too worried. What she is really worried about is Zhang Heng on the other side, especially when the latter just asked to go up, but he encountered the current in a blink of an eye.
But fortunately, Zhang Heng did not show any panic so far, and swam to the edge of the rock with Nelly.
After about a minute and a half, Nelly felt that the sea current had become smaller, so she gestured to ask Zhang Heng how much energy he had.
Zhang Heng glanced at the residual pressure gauge, which showed that he still had about 120 bar of gas. The three of them didn't stay underwater for a long time, and they were basically active at a depth of about 25 meters, and they didn't dive too deep. Therefore, the gas in the gas cylinder is not consumed much, and it is still far away from the warning line.
But since Zhang Heng has decided to go up, Ni Li, as a dive guide, of course has no reason to continue diving. However, before going up, the two of them still need to meet up with Han Lu at the rock wall.
Unlike the relatively clear sea water before, because of the influence of the sea current, a lot of sediment and impurities were brought up, and the visibility in the water became very low. Nelly turned on her flashlight again, but it was not known whether it was due to insufficient power, the flashlight in her hand flickered several times this time before it gradually stabilized.
However, when Nelly moved the flashlight to the rock wall where Han Lu was, she suddenly found that the latter was no longer there.
Nelly blinked her eyes, as if she couldn't believe what she saw, because Han Lu was the first to find a place to fix her body when the downcurrent came, and it was obvious that she had already escaped from the situation at that time. Dangerous, the three of them only separated for less than two minutes afterwards, there was no reason for Han Lu to leave this position in such a short time.
Nelly then turned the flashlight to other nearby directions, looking for the figure of Han Lu, but none of them received any goods, and at this moment, Nelly saw Zhang Heng gesturing to her, pointing to the top of his head.
Nelly thought it was Zhang Heng who discovered Han Lu's location, but when she looked up, she saw a strange scene that she had never seen in her many years of diving experience. Keep turning red.
Is this a red tide
Nelly lives by the sea. Although she has never seen a red tide with her own eyes, she is no stranger to this natural phenomenon. Red tides are usually caused by some phytoplankton, bacteria, or protozoa in the seawater that explode in a short period of time. Caused by high concentration, it will change the color of seawater and cause great harm to the environment.
However, this sea area is a famous diving spot on Yonaguni Island. The residents on the island have always attached great importance to the ecological environment. Over the years, there has never been a red tide in the nearby sea area, and the red tide generally affects the upper sea water. Nilly found that The red patch above their heads is rapidly approaching them.
Soon the two were surrounded by red sea water, the color of these sea water was actually very close to human blood, it was very infiltrating to be in it, and the most important thing was that they would further reduce the visibility, now Ni Li could only see a distance of less than two meters in front of her, and even the figure of Zhang Heng beside her became indistinct.
Even with Nelly's rich diving experience, she couldn't help feeling a little anxious now. The main reason was that this strange "red tide" appeared not too early or too late, and it happened to be at the pass where they were looking for Han Lu. Work suddenly became difficult.
Nelly wanted to bring Zhang Heng up first, and then come back to look for Han Lu by herself, because Zhang Heng had already asked her to ascend before the downwell, but it takes time for divers to ascend, because the pressure at different depths is different. At greater depths, nitrogen dissolves into the blood.
At this time, it is mainly the danger of nitrogen drunkenness mentioned above. At this moment, nitrogen gas is in a dissolved state in the blood, and if the pressure decreases rapidly, the nitrogen gas dissolved in the blood will precipitate and cause thrombus. Divers suffer from diving sickness, which can directly explode their lungs.
Therefore, when ascending from the water, there needs to be a safety stop. It will take seven minutes at the earliest after Nelly sends Zhang Heng to the boat and returns, not to mention whether she can get her wish back in the blood-red water. At the current location, it was hard to say whether Han Lu was still nearby at that time, and the remaining gas in her gas cylinder might not be enough to support her search for too long.
In normal times, Nelly could of course choose to take Zhang Heng to look for Han Lu together, but because of the influence of this weird red tide, the two of them may not be able to see each other as long as they are separated by a little distance. Even in such an environment, Nelly didn't have the confidence to take good care of Zhang Heng while she was looking for Han Lu.
Han Lu has already disappeared, so don't lose Zhang Heng at that time.
After a short thought, Nelly decided to take Zhang Heng up first, because she still had luck in her heart. Maybe Han Lu had already returned to the boat before them, and they would be able to see each other when they surfaced. , and to be honest, even if she takes Zhang Heng to take the risk to find Han Lu now, it's just luck.
But just when Nelly was about to take Zhang Heng up together, she seemed to catch a glimpse of a dark shadow flashing past her from the corner of her left eye.
Could it be Han Lu? A gleam of hope was born in Nelly's heart again. Although the black figure just passed by quickly, she still saw a rough outline, which indeed looked like a person wearing a diving suit.