Flashcard library · Earth & Climate Science · PaperFren

Late Tang hydroclimate swings strained northern China

Cooler, drier, and flood-prone conditions after 800 CE made Yellow River crop and supply networks increasingly fragile.

Keep what you just learned

Save these 11 cards to your NoteFren library. Your first review starts right away, and each card links back to the study it came from.

Which century marks the late Tang hydroclimatic downturn emphasized here?

After 800 CE, especially the 9th and early 10th centuries, conditions became cooler and drier.

What rainfall line bounds the farming–pastoral transition?

The present-day 400 mm/year isohyet.

How much of southeastern Yellow River annual rain falls in June–August under a strong EASM?

Just over 50%.

What happened to harvest grades in the first half of the 9th century?

They ranged from very poor to at most average, with particularly poor harvests between 800 and ~840 CE.

What hydroclimate sequence occurred around 880–900 CE then after 900 CE?

Above-normal runoff and flood risk ~880–900 CE, then a rapid runoff and precipitation decline after 900 CE.

How frequent can documentary floods be in dry, cool intervals?

Up to three events per year, with n > 1500 floods recorded over the last millennia.

What three vulnerability mechanisms do the authors highlight?

Millet-to-wheat/rice shift; new northern garrisons needing long-distance supply; prolonged northern droughts compromising those routes.

What streamflow archive fed the drought–flood model?

A Yellow River streamflow reconstruction (800–2000 CE) based on tree-ring data.

How many environmental-response bins and towns were used?

53 runoff bins and 31 Tang towns.

When did the dynasty finally collapse in their narrative?

907 CE, after drought, flood, and supply-network stress compounded political turmoil.

By the mid-8th century, how much of army grain did military farms supply?

Only 20%; most grain and fodder came from state purchases and long-distance transport.