1/100 of 1% of the world's oceans is a cube 32 miles on each side [0]. This volume of salt would weigh 317 billion tons [1]. World commercial production is .25 billion tons of salt [2].

So, to raise salinity by .01%, we'd need 1268 years of normal production (plus some when you exclude sea-water extraction).

[0] http://www.wolframalpha.com/input/?i=(volume+of+the+world%27...

[1] http://www.wolframalpha.com/input/?i=31956+cubic+miles+of+sa...

[2] http://www.saltinstitute.org/salt-101/production-industry/