They took a rock core from the east coast, which has excellent sediment records-good evidence of extreme seasonal variations.

他们在东海岸采集了一块岩心，这块岩心具有极好的沉积物记录——这是极端季节变化的充分证据。

As well as seasonal variations, it's been observed that the frequency of whale song has been dropping over the last few decades.

除了周期性变化外，科学家还发现在过去的几十年里，鲸鱼“歌唱”的频率也在下降。

These seasonal variations matter more for established viruses.

这些季节性变化对于已建立的病毒更为重要。

Now, there is a little bit less seasonal variation in oxygen in the Southern Hemisphere.

现在， 南半球氧气的季节性变化略有减少。

The seasonal variation in temperature depends upon latitude and how far away  from the ocean the place is.

温度的季节性变化取决于纬度以及该地距离海洋的距离。

Places further away from the equator or ocean have greater seasonal  variation than those that are closer to one or the other.

距离赤道或海洋较远的地方比距离其中一者较近的地方季节变化更大。

The study found that the participants experienced seasonal variations in their rapid eye movement sleep, also known as REM sleep, as well as in their slow wave sleep, also known as deep sleep.

研究发现，参与者在快速眼动睡眠（也称为 REM 睡眠）和慢波睡眠（也称为深度睡眠）中经历了季节性变化。

Through oysters, I'd gotten to know every inch of my farm's seafloor, and by growing plants vertically, I learned the patterns and seasonal variations of the full water column.

通过牡蛎，我了解了我农场海底的每一寸，通过垂直种植植物， 我了解了整个水柱的模式和季节变化。