No, it isn’t! On average a kilogram of seawater has about 35 grams of salt in it, or as oceanographers often say, the salinity averages about 35 parts per thousand (ppt). However, this can vary from much lower levels near the mouths of rivers up to levels exceeding 40 ppt in places like the Red Sea, where there is a lot more precipitation than evaporation. In some very special places, like at the bottom of the Red Sea, one might even find water with salinity of 200 ppt. In the open ocean, 38 ppt is about as high as one would usually measure. Figure 1 of this paper shows a map of how salinity can vary at the ocean surface , and Figure 5 shows an example of how it varies beneath the ocean surface: https://tos.org/oceanography/article/on-the-factors-driving-upper-ocean-salinity-variability-at-the-western-edge.
Compared to fresh water, all ocean water may just seem “salty”, but the saltiness of the ocean, typically called “salinity”, varies both over the horizontal extent of the oceans and with depth.
The ocean is salty because a variety of salts like sodium chloride (common table salt) are dissolved in the water. The salinity can be described in terms of grams of salt per 1000 grams of water, or parts-per-thousand (ppt). A typical ocean salinity value is 35 ppt. For comparison, drinking water would have a value of about 0.5 ppt. So ocean water is 70 times more salty!
The salinity varies from ocean to ocean. For example the Atlantic Ocean is the saltiest, with average surface salinity as high as 37 ppt, whereas the north Pacific Ocean has average surface salinity of about 33 ppt. Salinity changes with depth can be similar of similar magnitude.
No! In fact, the salinity, or “saltiness” of water is one of the main features that oceanographers use to distinguish different water masses. Water masses are the different “groupings” of water within our oceans, with their own individual temperature and salinity signatures. You can ask Ms. Durkin more about water masses if you want to learn more, or leave a question for the physical oceanographers!
The Arctic Ocean is the freshest (or least salty) of the oceans. This is due to the melting of the ice in the Arctic and high river inflow compared to other oceans, both of which are sources of freshwater (e.g. little to no salt).
The saltiest ocean is the Atlantic Ocean. This is because it has minimal sources of freshwater flowing into it, and because it is very warm. When the water is warmer, there is more evaporation. Evaporation removes freshwater from the ocean, but leaves behind the salt. In the end, evaporation dilutes the Atlantic Ocean and leaves behind quite a lot of salt!
For images of the world’s ocean salinity, and to learn more about ocean salinity, visit this NASA website: https://salinity.oceansciences.org/
No, it isn’t! On average a kilogram of seawater has about 35 grams of salt in it, or as oceanographers often say, the salinity averages about 35 parts per thousand (ppt). However, this can vary from much lower levels near the mouths of rivers up to levels exceeding 40 ppt in places like the Red Sea, where there is a lot more precipitation than evaporation. In some very special places, like at the bottom of the Red Sea, one might even find water with salinity of 200 ppt. In the open ocean, 38 ppt is about as high as one would usually measure. Figure 1 of this paper shows a map of how salinity can vary at the ocean surface , and Figure 5 shows an example of how it varies beneath the ocean surface:
https://tos.org/oceanography/article/on-the-factors-driving-upper-ocean-salinity-variability-at-the-western-edge.
Compared to fresh water, all ocean water may just seem “salty”, but the saltiness of the ocean, typically called “salinity”, varies both over the horizontal extent of the oceans and with depth.
The ocean is salty because a variety of salts like sodium chloride (common table salt) are dissolved in the water. The salinity can be described in terms of grams of salt per 1000 grams of water, or parts-per-thousand (ppt). A typical ocean salinity value is 35 ppt. For comparison, drinking water would have a value of about 0.5 ppt. So ocean water is 70 times more salty!
The salinity varies from ocean to ocean. For example the Atlantic Ocean is the saltiest, with average surface salinity as high as 37 ppt, whereas the north Pacific Ocean has average surface salinity of about 33 ppt. Salinity changes with depth can be similar of similar magnitude.
No! In fact, the salinity, or “saltiness” of water is one of the main features that oceanographers use to distinguish different water masses. Water masses are the different “groupings” of water within our oceans, with their own individual temperature and salinity signatures. You can ask Ms. Durkin more about water masses if you want to learn more, or leave a question for the physical oceanographers!
The Arctic Ocean is the freshest (or least salty) of the oceans. This is due to the melting of the ice in the Arctic and high river inflow compared to other oceans, both of which are sources of freshwater (e.g. little to no salt).
The saltiest ocean is the Atlantic Ocean. This is because it has minimal sources of freshwater flowing into it, and because it is very warm. When the water is warmer, there is more evaporation. Evaporation removes freshwater from the ocean, but leaves behind the salt. In the end, evaporation dilutes the Atlantic Ocean and leaves behind quite a lot of salt!
For images of the world’s ocean salinity, and to learn more about ocean salinity, visit this NASA website: https://salinity.oceansciences.org/