Observed trends in winegrape maturity in Australia

Abstract

An extensive assessment of historical trends in winegrape maturity dates from vineyards located in geographically diverse winegrape growing regions in Australia has been undertaken. Records from 44 vineyard blocks, representing a range of varieties of Vitis vinifera L., were accessed. These comprise 33 short-term datasets (average 17 years in length) and 11 long-term datasets, ranging from 25 to 115 years in length (average 50 years). Time series of the day of the year grapes attain maturity were assessed. A trend to earlier maturity of winegrapes was observed in 43 of the 44 vineyard blocks. This trend was significant for six out of the 11 long-term blocks for the complete time period for which records were available. For the period 1993-2009, 35 of the 44 vineyard blocks assessed displayed a statistically significant trend to earlier maturity. The average advance in the phenology was dependent on the time period of observation, with a more rapid advance over more recent decades. Over the more recent 1993-2009 period, the average advance was 1.7 days year, whereas for the period 1985-2009 the rate of advance was 0.8 days yr À1 on average in the 10 long-term vineyard blocks assessed for cross-regional comparison. The trend to earlier maturity was associated with warming temperature trends for all of the blocks assessed in the study.

Drought reconstruction based on grape harvest dates for the Czech Lands, 1499-2012

“…We detected a statistically significant trend towards earlier GHDs, higher total potential evapotranspiration and mean temperatures. A trend towards earlier maturity of wine grapes has been observed in several countries as a result of recent climate change (Webb et al 2011, Malheiro et al 2013, Vršič et al 2014). Earlier maturity of wine grapes has been associated with increasing temperature and decreasing soil water content during the growing season in Australia (Webb et al 2012), but this conclusion was apparently inconsistent with long-term trends of annual rainfall (White 2013).…”

Identifying the future water and salinity risks to irrigated viticulture in the Murray-Darling Basin, South Australia

“…The most critical impact of climate change observed at the global scale is the advancement of maturity of grapes by 4-8 days (Jones et al, 2005;Webb et al, 2011). Webb et al (2007) projected a 50-day advancement in the maturity of grapes in the Coonawarra region of South Australia by 2050.…”

Distinct Global Patterns of Strong Positive and Negative Shifts of Seasons over the Last 6 Decades

“…The study shows an advanced maturity of wine grapes, associated with an earlier onset of spring in Southeast Australia. However, a delayed maturity of 0.1 days per year was observed at a site located in Southwest Australia [41].…”