The Athenians recognised how critical the situation had become and in BC appointed Solon, a middle class Athenian who d made his trade, as arkhon. The Athenians had opted the hoplite method of fighting , which brought together and armed many male Athenians. Chapter East versus West The Persian Wars The Persians made camp close to the sea in the bay of Marathon with a large marsh behind them and they marched out toward the small Athenian army with the sea to their left, as Figure illustrates. They erected a monument at the sacred site of Delphi as a visual symbol of their new unity. Many Athenian aristocrats didn t trust Socrates, and he d refused to cooperate with the tyrants. Although ing any interference in the Greek islands, the next ten years Sparta continually attacked the Greek towns in the Peloponnese.
Back in the mer of , scientists studying the vast and in some places mile thick Greenland ice sheet observed something that can be ed breathtaking.
Due to meltwater, lakes atop the ice sheet in the mer scientists them supraglacial lakes and they can grow to be quite large. And in July , one large lake, over square miles in area, suddenly vanished. It lost most of its water in under two hours researchers calculated that the rate of drainage exceeded the average flow rate over Niagara Falls.
There was one place all that water could have gone down into the ice sheet, where researchers feared it could lubricate its base and hasten its slide into the ocean. Little understood effects like this, they wrote, could d to the dynamism and rapidity with which Greenland which contains enough ice to raise sea levels t responds to global warming by melting and pouring water into the ocean.
, many years later, scientists MIT, the Woods Hole Oceanographic Institution and several other universities including a number who wrote that original study think they ve explained how these great glacial lake vanishings happen. And they ve done so by studying that same, rapidly vanishing lake North Lake, they it.
The new research, published today in the journal Nature, finds that gigantic cracks beneath some meltwater lakes precisely because water has already gotten underneath the ice sheet elsewhere lubricating it and making it slip. This, in turn, cracks new pathways that inject still more water below the surface, further helping ice to slide seaward.
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