Ice cores in the northern and southern hemisphere display sulfate spikes associated with Samalas. The signal is the strongest in the southern hemisphere over the last 1000 years; one reconstruction even considers it the strongest of the last 2500 years. It is about eight times stronger than that of Krakatau. In the northern hemisphere it is only exceeded by the signal of the destructive 1783/1784 Laki eruption; The ice core sulfate spikes have been used as a time marker in chronostratigraphic studies. Ice cores from Illimani in Bolivia contain thallium and sulfate spikes from the eruption. For comparison, the 1991 eruption of Pinatubo ejected only about a tenth of the amount of sulfur erupted by Samalas. Sulfate deposition from the Samalas eruption has been noted at Svalbard, and the fallout of sulfuric acid from the volcano may have directly affected peatlands in northern Sweden. In addition, the sulfate aerosols may have extracted large amounts of the beryllium isotope 10Be from the stratosphere; such an extraction event and the subsequent deposition in ice cores may mimic changes in solar activity. The amount of sulfur dioxide released by the eruption has been estimated to be 158 ± 12 million tonnes. The mass release was greater than for the Tambora eruption; Samalas may have been more effective at injecting tephra into the stratosphere, and the Samalas magma may have had a higher sulfur content. After the eruption, it probably took weeks to months for the fallout to reach large distances from the volcano. When large scale volcanic eruptions inject aerosols into the atmosphere, they can form stratospheric veils. These reduce the amount of light reaching the surface and cause colder temperatures, which can lead to poor crop yields. Such sulfate aerosols in the case of the Samalas eruption may have remained at high concentrations for about three years according to findings in the Dome C ice core in Antarctica, although a smaller amount may have persisted for an additional time.