This is the supplementary answer to that of drooze ( I think he finally hit the direct answer. )
As he said, according to this site( Japanese ), Nanshi records multiple quite unusual events occurred in Liang Dynasty ( English ).
Quote ( from the above Japanese source )
In the intercalary December, 534AD, we heard the lightening sound twice at South West. ( Nanshi 184.108.40.206 )
This would be the reference to the volcano explosion of the Krakatoa, in Indonesia, that occurred in 535 AD, though I assume people in Liang Dynasty would've forgotten such lightenings soon from their memories. So those, the unusual lightening sounds, seemed.., should have been nothing to do with the living of people. But parallels of extraordinary climate events occurred multiple time since the sound. In the next year, in October, yellow dusts amounted like snow ( Nanshi 220.127.116.11 ). We have no clue now to confirm that this was the dust of the result of the volcano explosion that happened in the previous year. But these dusts are recorded in Nanshi, observed in the next year, in November 536 ( Nanshi 18.104.22.168 ), on the first of February 537, ( Nanshi 22.214.171.124 ), on 4th of January in 550 ( Nanshi, 126.96.36.199 ).
「There seems to be something wrong」, I assume Chinese people of Liang Dynasty must had begun to think. But the time was too late, the chains of the extravagant disasters already started. In the summer of the 537, Liang people suffered from the extraordinary cold summer, and in the same year, in June in Quingzhou, people suffered from the severe frost damage, ( Nanshi 188.8.131.52 ) and in the same year, in July, in the same Quingzhou snow fell thus it had enormous impact on the production of crops. ( Nanshi 184.108.40.206 ). If you account for Quingzhou province, it is situated at the same latitude of 37 degree in the northern hemisphere, same with Japanese Iwaki City, and the U.S's California, ans also with that of Syria. It would be equivalent with that snow falls in August at all these areas at the same time.
Regardless of AlphaD's answer, who could potentially answer to the OP's question directly, but unfortunately as in my comment to him, I would like to continue. ( Or therefore ).
As expected normally, famine happened in 538 ( Nanshi 220.127.116.11 ), and the Imperial Court ( I would like not to use the word "government", since there was not a "government" in the modern sense. ) decided on the 30th of the January of the year, to implement an amnesty to the tax-cut to its' 12 southern provinces where famines were observed, especially to those who were unable to pay the tax. ( Nanshi 18.104.22.168 ). However, the extraordinarily strange climate continued, finally the Emperor declared on November 541, 「 「 Applying the Road Of Heaven in order to share the benefit of the earth 」 is the old proverb by sages. Except for the lands for the Imperial Household, let us give all the abandoned lands and mulberry fields and houses to the poor. We will look into the labor power of these poor, and in accordance with it, let's give them the appropriate size of arable lands. In accordance with our survey we heard, these riches and mighty people recently exploit our Imperial Houshold's lands, imposing heavy farm rents to the poor, so that damaging our administrative functions to the unparalleled degree. From now on, we will prohibit these mighty people from holding the Imperial Houses' lands, except for the already exploited. If the riches, in cooperation with the poor, try to cultivate the ( abandoned ) lands, this prohibition will be annulled. ( Nanshi 22.214.171.124 ).
I would like to skip the uprising part since the translation of the uprising which occurred at many areas at Liang Dynasty is too difficult with sorry.
Now, moving onto the Cannibalism which was observed in Liang Dynasty ( not in Wei's dynasty ( which is the difference between mine and Lars' ))
These uprisings ( which I skipped to translate ) were quenched happily, but the catastrophic climate didn't stop at all. In September 545, an earthquake happened, in November of the same year, huge snow fell and it amounted to about 99㎝, ( Nanshi 126.96.36.199 ). Nanshi writes, at 3 o'clock? in December in 548, people saw the sky was broken and saw the beam of the fire like a thunder. ( Nanshi 188.8.131.52 ). I don't know what this description by Nanshi would imply, but people in the Liang Dynasty might have seen another volcano explosion which became later the cause of the fall of the yellow dust in 550 ( which was previously mentioned ). Famine erupted elsewhere in the dynasty, so catastrophic it stretched to over 9 rivers? in the dynasty, there appeared the cannibalism, Nanshi reports the death toll of 145 people by it, ( Nanshi 184.108.40.206 ), in addition to it, from the spring to the summer of 550, a huge drought happened, people ate people everywhere. The famine was so devastating near the capitol, Nanshi reports ( Nanshi 220.127.116.11 ) The economics of the Liang Dynasty completely went out of control, which led to the collapse of the dynasty, replaced by the new Chen Dynasty, caused by Hou Jing.
In "my research" there is no description about the death toll of 70-80% by Nanshi. Either the blogger might have skipped to describe it intentionally or may be for another reason. )
I would like to lastly describe about the Beishi.
According to Beishi, the climate change was like this.
On the other hand, according to Beishi, in northern Wei too, abnormal climate started so that at 15-17 o'clock? on Saturday? in May 535, an Imperial decree was issued due to the drought. It orders, 「 From Luoyang ( 洛陽 ) to Chang'an ( 長安 ) and to the all provinces including all the counties, one should bury the corpses. 」( Beishi 18.104.22.168.2 ). However the drought could not be stopped and continued, even for 5 months in the summer of the same year, a dramatic drought occurred. The imperial court ordered that water be provided to all the people at the gate of Chang'an and that of the Imperial palace, as well as the at the gates of all the imperial offices, ( Beishi 22.214.171.124.2 ). Furthermore, what worsened the situation was, in 4 provinces, 並、肆、涿、建 ( untranslatable ), there was a frost in August, which caused the pandemic of the great famine, ( Beishi 126.96.36.199.3 ), therefore on the day of 戊申 ( unknown ), in November in the winter, Court decided to dispatch the imperial monitors to observe those who were damaged by the famine around The Yellow River. ( Beishi 188.8.131.52.3 ). The pandemic reached to the unimaginable level, Beishi records frogs croaking on the branch of the tree, mass flood occurred in Shandong province, in exchange for the drought which happened previously, in the summer of 538.
This line coincidentally speaks the same devastating events that occurred in Northern Wei described in Lars' answer.
I think drooze made a direct answer to all of the OP's question completely.